Big Ideas Math - Algebra 1, A Common Core Curriculum

Published by Big Ideas Learning LLC
ISBN 10: 978-1-60840-838-2
ISBN 13: 978-1-60840-838-2

Chapter 5 - Solving Systems of Linear Equations - 5.1-5.4 - Quiz - Page 260: 8

Answer

The solution is $(4,-1)$.

Work Step by Step

The given system of equations is $x+3y=1$ ...... (1) $5x+6y=14$ ...... (2) Multiply equation (1) by $-2$. $-2(x+3y)=-2(1)$ Use distributive property. $-2x-6y=-2$ ...... (3) Add equation (2) and (3). $\Rightarrow 5x+6y-2x-6y=14-2$ Add like terms. $\Rightarrow 3x=12$ Divide each side by $3$. $\Rightarrow \frac{3x}{3}=\frac{12}{3}$ Simplify. $\Rightarrow x=4$ Substitute $4$ for $x$ in equation (1). $\Rightarrow 4+3y=1$ Subtract $4$ from each side. $\Rightarrow 4+3y-4=1-4$ Simplify. $\Rightarrow 3y=-3$ Divide each side by $3$. $\Rightarrow \frac{3y}{3}=\frac{-3}{3}$ Simplify. $\Rightarrow y=-1$ Check $(x,y)=(4,-1)$ Equation (1): $\Rightarrow x+3y=1$ $\Rightarrow 4+3(-1)=1$ $\Rightarrow 4-3=1$ $\Rightarrow 1=1$ True. Equation (2): $\Rightarrow 5x+6y=14$ $\Rightarrow 5(4)+6(-1)=14$ $\Rightarrow 20-6=14$ $\Rightarrow 14=14$ True. Hence, the solution is $(4,-1)$.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.