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For each linear system of equations, identify the

solution; if there is no solution, put an asterisk (*) in
the boxes for the coordinate values.
System A has a solution at
System B has a solution at(
System C has a solution at
A. y=x+5
V = 3x -3
B.
-2V
-1+7
8V = 4x + 10
C. y=
-3x
x+ y = 16

For each linear system of equations, identify the solution; if there is no solution-example-1
User Malvim
by
2.4k points

1 Answer

28 votes
28 votes

Step-by-step explanation

First equation:

y = x + 5

y = 3x - 3


\mathrm{Substitute\:}y=3x-3
\begin{bmatrix}3x-3=x+5\end{bmatrix}
\mathrm{Add\:}3\mathrm{\:to\:both\:sides}
x-3+3=x+5+3

Simplify:


3x=x+8
\mathrm{Subtract\:}x\mathrm{\:from\:both\:sides}
3x-x=x+8-x

Simplify:


2x=8
\mathrm{Divide\:both\:sides\:by\:}2
(2x)/(2)=(8)/(2)

Simplify:


x=4
\mathrm{For\:}y=3x-3
\mathrm{Substitute\:}x=4
y=3\cdot \:4-3
\mathrm{Simplify}
y=9

Therefore, System A has a solution at (4,9)

Second equation:


\begin{bmatrix}-2y=-x+7 \\ 8y=4x+10\end{bmatrix}
\mathrm{Divide\:both\:sides\:by\:}-2
(-2y)/(-2)=-(x)/(-2)+(7)/(-2)

Simplifying:


y=-(-x+7)/(2)
\mathrm{Substitute\:}y=-(-x+7)/(2)
\begin{bmatrix}8\left(-(-x+7)/(2)\right)=4x+10\end{bmatrix}

Removing the parentheses:


=-8\cdot (-x+7)/(2)

Multiplying fractions:


=-(\left(-x+7\right)\cdot \:8)/(2)
\mathrm{Divide\:the\:numbers:}\:(8)/(2)=4
-4\left(-x+7\right)=4x+10
\mathrm{Refine\:}-4\left(-x+7\right)=4x+10
-38=0
-38=0\:\mathrm{\:is\:false,\:therefore\:the\:system\:of\:equations\:has\:no\:solution}

System B has a solution at (*,*)

Third equation:


\begin{bmatrix}y=-3x\\ x+y=16\end{bmatrix}
\mathrm{Substitute\:}y=-3x
\begin{bmatrix}x-3x=16\end{bmatrix}
\begin{bmatrix}-2x=16\end{bmatrix}
\mathrm{Divide\:both\:sides\:by\:}-2
(-2x)/(-2)=(16)/(-2)

Simplify the expression:


x=-8
\mathrm{For\:}y=-3x
\mathrm{Substitute\:}x=-8
y=-3\left(-8\right)
\mathrm{Simplify}
y=24
\mathrm{The\:solutions\:to\:the\:system\:of\:equations\:are:}
y=24,\:x=-8

Therefore, System C has a solution at (-8,24)

User Chenchuk
by
3.1k points