Question

-14x + 15y = 15
-21x - 20y = -10
Use substitution to find the x and y coordinates.

Answer 1

-14x + 15y = 15
-14x + 14x + 15y = 14x + 15
15y = 14x + 15
15 15
y = ¹⁴/₁₅x + 1
-21x - 20y = -10
-21x - 20(¹⁴/₁₅x + 1) = -10
-21x - 20(¹⁴/₁₅x) - 20(1) = -10
-21x - 18²/₃x - 20 = -10
-39²/₃x - 20 = -10
+ 20 + 20
-39²/₃x = 10
-39²/₃ -39²/₃
x = ⁻³⁰/₁₁₉
y = ¹⁴/₁₅x + 1
y = ¹⁴/₁₅(⁻³⁰/₁₁₉) + 1
y = ⁻²⁸/₁₁₉ + 1
y = ⁹¹/₁₁₉
(x, y) = (⁻³⁰/₁₁₉, ⁹¹/₁₁₉)