Question

when solving the following system of equations by substitution what would be a correct first step x=y–7 3x+15y=-1

Answer 1

Answer:

The first step is to replace the value of x from the first equation with x in the second equation:

x=y-7

3x+15y=-1

3(y-7)+15y=-1        

3y-21+15y=-1

18y=-1+21

18y=20

y= $\frac{20}{18}$ = $\frac{10}{9}$

x= $\frac{10}{9}$ $- 7$

x=$- \frac{53}{9}$