Answer:
100
Step-by-step explanation:
A ) y = 2(3) + 7
y = 15
b ) y = 2(-3) + 7
y = 1
Answer:

at least means it need to be more or the lowest it can be is 18
x² - 80 = 0
Add 80
to each side: x² = 80
Square root
each side: x = √80
Look it up: x = + 8.944... (rounded)
and
x = - 8.944... (rounded).
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Here's a cleaner solution:
x² - 80 = 0
Add 80
to each side: x² = 80
Square root
each side: x = √80
But 80 = 16 · 5
So √80 = √16 · √5
√16 = 4, so x = 4 √5