Answer:
x=-5, y=2. (-5, 2).
Step-by-step explanation:
2x+y=-8
3x-5y=-25
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5(2x+y)=5(-8)
3x-5y=-25
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10x+5y=-40
3x-5y=-25
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13x=-65
x=-65/13
x=-5
2(-5)+y=-8
-10+y=-8
y=-8-(-10)=-8+10=2
It takes about 4 days for the temperature to decrease by 9°F.
An equation is an expression that shows the relationship between two or more variables or numbers.
Let x represent the number of days. Given that the temperature drop decreased by 1 1/2°F each day (- 1 1/2), for it to decrease by 9°F (-9):
-1 1/2 * x = -9
-1.5x = - 9
x = 4 days
It takes about 4 days for the temperature to decrease by 9°F.
A)
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B)
Or
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C)
Max height is the vertex
convert to vertex form (y=a(x-h)^2+k) by completeing the square
h(t)=-16(t²-4t)+80
h(t)=-16(t²-4t+4-4)+80
h(t)=-16((t-2)²-4)+80
h(t)=-16(t-2)²+64+80
h(t)=-16(t-2)²+144
vertex is (2,144)
at t=2, the height is 144
max height is 144ft
