The problem gives you X, so replace X witht he given vaule and solve for y:
y = -0.1x^2 + 4X
X = 40
y = -0.1(40)^2 +4(40)
y = -0.1(1600) + 160
y = -160 + 160
y = 0
Answer:
its the last one I think.
Answer:
A right triangle with degrees 20, 70, 90.
Step-by-step explanation:
Let X = science homework.
Then math homework would be 3x ( three times as long).
Now you have math plus science = 64 minutes:
x + 3x = 64
Combine like terms:
4x = 64
Divide both sides by 4:
x = 64 / 4
x = 16
He spent 16 minutes on science and 48 minutes on math.
