The problem has three parts: (a) Factorize completely $2\pi h + 2\pi r^2$. (b) Express $\frac{4}{x+5} - \frac{3}{x}$ as a single fraction in its simplest form. (c) Solve the simultaneous equations: $2x+3y=13$ and $x+2y=8$.

AlgebraFactorizationRational ExpressionsSimultaneous EquationsLinear Equations
2025/6/11

1. Problem Description

The problem has three parts:
(a) Factorize completely 2πh+2πr22\pi h + 2\pi r^2.
(b) Express 4x+53x\frac{4}{x+5} - \frac{3}{x} as a single fraction in its simplest form.
(c) Solve the simultaneous equations: 2x+3y=132x+3y=13 and x+2y=8x+2y=8.

2. Solution Steps

(a) Factorizing 2πh+2πr22\pi h + 2\pi r^2:
We can factor out the common factor 2π2\pi from both terms.
2πh+2πr2=2π(h+r2)2\pi h + 2\pi r^2 = 2\pi(h + r^2).
Alternatively, if rr represents radius, it should be 2πrh+2πr22\pi rh + 2\pi r^2. In that case, we factor out 2πr2\pi r:
2πrh+2πr2=2πr(h+r)2\pi rh + 2\pi r^2 = 2\pi r(h + r).
Given the prompt, it looks like the intended question was 2πrh+2πr22\pi rh + 2\pi r^2.
(b) Expressing 4x+53x\frac{4}{x+5} - \frac{3}{x} as a single fraction:
To subtract the two fractions, we need a common denominator, which is x(x+5)x(x+5).
4x+53x=4xx(x+5)3(x+5)x(x+5)\frac{4}{x+5} - \frac{3}{x} = \frac{4x}{x(x+5)} - \frac{3(x+5)}{x(x+5)}
=4x3(x+5)x(x+5)= \frac{4x - 3(x+5)}{x(x+5)}
=4x3x15x(x+5)= \frac{4x - 3x - 15}{x(x+5)}
=x15x(x+5)= \frac{x - 15}{x(x+5)}
=x15x2+5x= \frac{x-15}{x^2 + 5x}
(c) Solving the simultaneous equations:
2x+3y=132x + 3y = 13 (1)
x+2y=8x + 2y = 8 (2)
From equation (2), we can express xx in terms of yy: x=82yx = 8 - 2y.
Substitute this into equation (1):
2(82y)+3y=132(8-2y) + 3y = 13
164y+3y=1316 - 4y + 3y = 13
16y=1316 - y = 13
y=1613y = 16 - 13
y=3y = 3
Now, substitute y=3y=3 into the equation x=82yx = 8 - 2y:
x=82(3)x = 8 - 2(3)
x=86x = 8 - 6
x=2x = 2
So, the solution is x=2x=2 and y=3y=3.

3. Final Answer

(a) 2πr(h+r)2\pi r(h+r)
(b) x15x(x+5)\frac{x-15}{x(x+5)}
x = 2
y = 3

Related problems in "Algebra"

We are given a 3x3 matrix $A$ and asked to find all the minors $|A_{ij}|$ of the matrix. The given m...

MatricesDeterminantsMinors
2025/7/29

A binary operation $*$ is defined on the set of real numbers $R$ by $m * n = m + n - \frac{1}{2}n$. ...

Binary OperationReal NumbersExpression Evaluation
2025/7/29

We are given a 4x4 matrix $A$ and asked to find its determinant $|A|$ and the (3,4) entry of its inv...

Linear AlgebraMatrix DeterminantMatrix InverseCofactor ExpansionAdjugate Matrix
2025/7/29

The problem is to solve the quadratic equation $55n^2 - 33n - 1940 = 0$ for the variable $n$.

Quadratic EquationsQuadratic FormulaRoots of Equation
2025/7/25

We need to solve the equation $\frac{x+6}{x+4} = \frac{-5}{3x}$ for $x$.

EquationsRational EquationsQuadratic EquationsSolving EquationsAlgebraic Manipulation
2025/7/24

The problem asks to factorize the quadratic expression $3x^2 - 2x - 1$.

Quadratic EquationsFactorizationAlgebraic Manipulation
2025/7/24

We are asked to solve four problems: (a) Expand and simplify the expression $6(2y-3) - 5(y+1)$. (b) ...

Algebraic SimplificationExponentsDifference of SquaresEquationsFactorization
2025/7/22

We are asked to simplify the expression $(a^{-2}b^3)^{-2}$, writing the answer with positive powers.

ExponentsSimplificationPower Rules
2025/7/22

A group of children bought a certain number of apples. If each apple is cut into 4 equal pieces and ...

System of EquationsWord Problem
2025/7/21

The problem asks to simplify the expression $\frac{x+1}{y} \div \frac{2(x+1)}{x}$.

Algebraic simplificationFractionsVariable expressions
2025/7/21