Answer:
While x = -7 and y = 4, x² - 3xy = 133.
Step-by-step explanation:
x² - 3xy
Substitute variables.
(-7)² - 3(-7)(4)
Square -7 remembering that (-x)² = x².
49 - 3(-7)(4)
Multiply -7 and 4.
49 - 3(-28)
Multiply -3 and -28.
49 + 84
Add 49 and 84.
133