The problem asks us to find the equation of a line $L_2$ that passes through a given point $P$ and is parallel to a given line $L_1$. We will solve problems 5 and 6. 5) $P(-1, 1)$ and $L_1: x - y + 5 = 0$ 6) $P(0, -2)$ and $L_1: x + y + 1 = 0$

GeometryLinear EquationsParallel LinesSlopePoint-Slope Form
2025/4/28

1. Problem Description

The problem asks us to find the equation of a line L2L_2 that passes through a given point PP and is parallel to a given line L1L_1. We will solve problems 5 and
6.
5) P(1,1)P(-1, 1) and L1:xy+5=0L_1: x - y + 5 = 0
6) P(0,2)P(0, -2) and L1:x+y+1=0L_1: x + y + 1 = 0

2. Solution Steps

5) Given point P(1,1)P(-1, 1) and line L1:xy+5=0L_1: x - y + 5 = 0.
We need to find a line L2L_2 that passes through PP and is parallel to L1L_1.
Since L2L_2 is parallel to L1L_1, their slopes are equal.
Rewrite L1L_1 in slope-intercept form: y=x+5y = x + 5. The slope of L1L_1 is m=1m = 1.
Therefore, the slope of L2L_2 is also m=1m = 1.
Using the point-slope form of a line, we have:
yy1=m(xx1)y - y_1 = m(x - x_1)
Substituting P(1,1)P(-1, 1) and m=1m = 1, we get:
y1=1(x(1))y - 1 = 1(x - (-1))
y1=x+1y - 1 = x + 1
y=x+2y = x + 2
Therefore, L2:xy+2=0L_2: x - y + 2 = 0.
6) Given point P(0,2)P(0, -2) and line L1:x+y+1=0L_1: x + y + 1 = 0.
We need to find a line L2L_2 that passes through PP and is parallel to L1L_1.
Since L2L_2 is parallel to L1L_1, their slopes are equal.
Rewrite L1L_1 in slope-intercept form: y=x1y = -x - 1. The slope of L1L_1 is m=1m = -1.
Therefore, the slope of L2L_2 is also m=1m = -1.
Using the point-slope form of a line, we have:
yy1=m(xx1)y - y_1 = m(x - x_1)
Substituting P(0,2)P(0, -2) and m=1m = -1, we get:
y(2)=1(x0)y - (-2) = -1(x - 0)
y+2=xy + 2 = -x
y=x2y = -x - 2
Therefore, L2:x+y+2=0L_2: x + y + 2 = 0.

3. Final Answer

5) xy+2=0x - y + 2 = 0
6) x+y+2=0x + y + 2 = 0

Related problems in "Geometry"

Show that $\vec{a} \times (\vec{b} \times \vec{a}) = (\vec{a} \times \vec{b}) \times \vec{a}$.

Vector AlgebraVector Triple ProductVector OperationsCross ProductDot Product
2025/6/17

The problem asks to find the area $S$ of a sector with radius $r = 4$ and arc length $l = 10$.

SectorAreaArc LengthGeometric Formulas
2025/6/17

The problem asks to identify the prism that can be formed from the given nets. We are given four dif...

PrismsNets3D ShapesCubesRectangular PrismsTriangular PrismsCylinders
2025/6/17

The problem asks to identify the prism formed by the given nets. The image shows four nets. The firs...

3D ShapesNetsPrismsCylindersCube
2025/6/17

We are given a triangle with one exterior angle of $130^\circ$ and one interior angle labeled as $x$...

TrianglesAnglesExterior AnglesInterior Angles
2025/6/17

We are given a triangle with two of its angles known. Angle A is $85^\circ$ and angle B is $68^\circ...

TrianglesAngle Sum PropertyLinear Equations
2025/6/17

We are given a circle with center O. CD is a tangent to the circle at point C. Angle CDB is given as...

CircleTangentAnglesAlternate Segment TheoremIsosceles Triangle
2025/6/17

The problem asks us to find the gradient of the line passing through each of the given pairs of poin...

Coordinate GeometrySlopeGradientLinear Equations
2025/6/17

We are given a pentagon with some information about its angles and sides. We need to find the size o...

PolygonsPentagonsAnglesIsosceles Triangle
2025/6/17

We are given a triangle with one exterior angle of $249^\circ$. Two of the interior angles of the tr...

TrianglesInterior AnglesExterior AnglesAngle Sum Property
2025/6/17