question

y=5x-11

2x+3y=18

Solve the system of equations by substitution.

simplify

$$\\2\times x \quad + \quad 3\quad \times\underbrace{y}_{=5x-11}=18 \\\\
2\times x \quad + \quad 3\quad \times (5x-11)=18\\\\
2\times x \quad + \quad 3\times 5x - 3\times 11 = 18$$

2x + 15x - 33 = 18

17x                 = 18 + 33

17x                 = 51

    x                 = 51 / 17

    x                 = 3

y = 5*x   - 11

y = 5*(3) - 11

y = 15     - 11

y = 4