Question

y=3x2y-5x=4 use the substitution method

Answer 1

We are given the system

$\begin{gathered} y=3x \\ 2y\text{ -5x=4} \end{gathered}$

and told to use substitution method to solve the system. We take the first equation and replace it in the second one. So we get

$2(3x)\text{ -5x=4}$

if we operate on the left hand side, we get

$2(3x)\text{ -5x=6x -5x=x}$

so we have the equation

$x=4$

now, we replace this value in the first equation. So we get

$y=3x=3(4)=12$

so the solution of the system is x=4 and y=12