WILL GIVE BRAINLIEST
20 POINTS

Answer:
x = - 3
Step-by-step explanation:
Given the 2 equations
y = [tex]\frac{1}{3}[/tex] x + 7 → (1)
y = 3x + 15 → (2)
Since both equations express y in terms of x, equate the right sides
3x + 15 = [tex]\frac{1}{3}[/tex] x + 7
Subtract [tex]\frac{1}{3}[/tex] x from both sides
[tex]\frac{8}{3}[/tex] x + 15 = 7 ( subtract 15 from both sides )
[tex]\frac{8}{3}[/tex] x = - 8 ( multiply both sides by 3 )
8x = - 24 ( divide both sides by 8 )
x = - 3