The image presents several math problems. We will solve them one by one. The problems are: 1. a) Expand and simplify $(n+4)^2 + (n-2)^2$ b) At an electrical shop, out of 92 people, 45 bought cables, and 58 bought sockets, while 14 asked prices without buying. Represent the information on a Venn diagram. Calculate the number of people who bought both sockets and cables. c) A straight line passing through points $(3,2)$ and $(4,5)$ intersects the y-axis at -23. Find the equation of the line.

AlgebraExpanding ExpressionsSimplifying ExpressionsVenn DiagramsLinear EquationsExponentsEquation SolvingKinematicsTrigonometrySimplifying Fractions
2025/6/10

1. Problem Description

The image presents several math problems. We will solve them one by one. The problems are:

1. a) Expand and simplify $(n+4)^2 + (n-2)^2$

b) At an electrical shop, out of 92 people, 45 bought cables, and 58 bought sockets, while 14 asked prices without buying. Represent the information on a Venn diagram. Calculate the number of people who bought both sockets and cables.
c) A straight line passing through points (3,2)(3,2) and (4,5)(4,5) intersects the y-axis at -
2

3. Find the equation of the line.

2. a) Solve for $x$ in the equation $(\frac{1}{4})^x = 8^{3x+2}$.

b) Given v2=u2+2asv^2 = u^2 + 2as, calculate the final velocity vv of a moving car with initial velocity u=30m/su = 30 m/s, acceleration a=5m/s2a = 5 m/s^2, and distance s=320ms = 320 m.
c) A hunter on top of a tree sees an antelope at an angle of depression of 3030^\circ. The height of the tree is 8m. Illustrate the information in a diagram. Find the distance between the hunter and antelope.

3. a) Simplify $\frac{2x-1}{3} - \frac{x-4}{4} + \frac{2x+1}{8}$.

2. Solution Steps

1. a) Expand and simplify $(n+4)^2 + (n-2)^2$:

(n+4)2=n2+8n+16(n+4)^2 = n^2 + 8n + 16
(n2)2=n24n+4(n-2)^2 = n^2 - 4n + 4
(n+4)2+(n2)2=(n2+8n+16)+(n24n+4)=2n2+4n+20(n+4)^2 + (n-2)^2 = (n^2 + 8n + 16) + (n^2 - 4n + 4) = 2n^2 + 4n + 20

2. b) Let $C$ be the set of people who bought cables, and $S$ be the set of people who bought sockets.

Total number of people = 92
C=45|C| = 45
S=58|S| = 58
Number of people who didn't buy anything = 14
Number of people who bought at least one item = 92 - 14 = 78
CS=C+SCS|C \cup S| = |C| + |S| - |C \cap S|
78=45+58CS78 = 45 + 58 - |C \cap S|
CS=45+5878=10378=25|C \cap S| = 45 + 58 - 78 = 103 - 78 = 25
The number of people who bought both sockets and cables is
2

5. Venn diagram: Draw two overlapping circles representing the sets $C$ and $S$. The intersection contains 25 elements. The part of $C$ not in $S$ contains $45-25 = 20$ elements. The part of $S$ not in $C$ contains $58-25=33$ elements. The area outside both circles contains 14 elements.

3. c) A straight line passing through points $(3,2)$ and $(4,5)$ intersects the y-axis at -

2

3. Find the equation of the line.

Slope of the line, m=5243=31=3m = \frac{5-2}{4-3} = \frac{3}{1} = 3.
The equation of the line in point-slope form is yy1=m(xx1)y - y_1 = m(x - x_1).
Using point (3,2)(3,2), y2=3(x3)y - 2 = 3(x - 3)
y2=3x9y - 2 = 3x - 9
y=3x7y = 3x - 7
The line intersects the y-axis at -7, not -23 as given in the problem.
Assuming the problem statement is correct. The equation has the form y=mx+cy = mx + c.
Since the line passes through (3,2)(3,2) and (4,5)(4,5), we have
2=3m+c2 = 3m + c
5=4m+c5 = 4m + c
Subtracting the equations gives 3=m3 = m. So, m=3m=3.
Plugging this into 2=3m+c2=3m+c, we get 2=3(3)+c2 = 3(3)+c, so 2=9+c2=9+c, and c=7c = -7.
However, the line intersects the y-axis at -
2

3. This is a contradiction. There is no linear equation that goes through $(3,2)$ and $(4,5)$ and has a y-intercept of -

2

3. Assuming the y-intercept of the line is -7, the equation is $y = 3x - 7$.

4. a) Solve for $x$ in the equation $(\frac{1}{4})^x = 8^{3x+2}$.

(14)x=(41)x=4x=(22)x=22x(\frac{1}{4})^x = (4^{-1})^x = 4^{-x} = (2^2)^{-x} = 2^{-2x}
83x+2=(23)3x+2=29x+68^{3x+2} = (2^3)^{3x+2} = 2^{9x+6}
22x=29x+62^{-2x} = 2^{9x+6}
2x=9x+6-2x = 9x + 6
11x=6-11x = 6
x=611x = -\frac{6}{11}

5. b) Given $v^2 = u^2 + 2as$, calculate the final velocity $v$ of a moving car with initial velocity $u = 30 m/s$, acceleration $a = 5 m/s^2$, and distance $s = 320 m$.

v2=u2+2asv^2 = u^2 + 2as
v2=(30)2+2(5)(320)=900+3200=4100v^2 = (30)^2 + 2(5)(320) = 900 + 3200 = 4100
v=4100=10041=104164.03m/sv = \sqrt{4100} = \sqrt{100 \cdot 41} = 10\sqrt{41} \approx 64.03 m/s

6. c)

Let hh be the height of the tree, h=8h=8 m. Let dd be the horizontal distance between the base of the tree and the antelope.
Since the angle of depression is 3030^\circ, we have tan(30)=8d\tan(30^\circ) = \frac{8}{d}.
d=8tan(30)=813=83d = \frac{8}{\tan(30^\circ)} = \frac{8}{\frac{1}{\sqrt{3}}} = 8\sqrt{3}
Let xx be the distance between the hunter and the antelope.
x2=82+(83)2=64+643=64+192=256x^2 = 8^2 + (8\sqrt{3})^2 = 64 + 64 \cdot 3 = 64 + 192 = 256
x=256=16x = \sqrt{256} = 16 meters

7. a) Simplify $\frac{2x-1}{3} - \frac{x-4}{4} + \frac{2x+1}{8}$.

The common denominator is
2

4. $\frac{2x-1}{3} - \frac{x-4}{4} + \frac{2x+1}{8} = \frac{8(2x-1)}{24} - \frac{6(x-4)}{24} + \frac{3(2x+1)}{24}$

=16x8(6x24)+6x+324=16x86x+24+6x+324= \frac{16x - 8 - (6x - 24) + 6x + 3}{24} = \frac{16x - 8 - 6x + 24 + 6x + 3}{24}
=(166+6)x+(8+24+3)24=16x+1924= \frac{(16 - 6 + 6)x + (-8 + 24 + 3)}{24} = \frac{16x + 19}{24}

3. Final Answer

1. a) $2n^2 + 4n + 20$

b) 25 people bought both sockets and cables. Venn diagram described above.
c) If we ignore the y-axis intersection at -23, the line is y=3x7y = 3x - 7.

2. a) $x = -\frac{6}{11}$

b) v=104164.03v = 10\sqrt{41} \approx 64.03 m/s
c) The distance between the hunter and the antelope is 16 meters.

3. a) $\frac{16x + 19}{24}$

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