7/8 of an hour is 52.5 minutes. 3/10 of 52.5 minutes is 15.75 minutes. They spent 15.75 minutes warming up and cooling down.
vertex = (3,- 5 )
given a quadratic in standard form : y = ax² + bx + c ( a ≠ 0 ), then
the x-coordinate of the vertex is
= - 
y = x² - 6x + 4 is in standard form
with a = 1, b = - 6 and c = 4, hence
= - 
= 3
substitute this value into the equation for y- coordinate
y = 3² - 6(3) + 4 = 9 - 18 + 4 = - 5
vertex = (3, - 5 ) → second table
Area of the base = 1/2 * 10 * 5sqrt3 = 25 sqrt3
Total surface area = 25 sqrt3 + 3 * 1/2 * 10 * slant height = 214.5
25 sqrt3 + 15h = 214.5
15h = 214.5 - 25 sqrt3
h = (214.5 - 25sqrt3() / 15
= 11.41 cm to nearest hundredth
Basically, you need to calculate "x" correct?
The tangent of (52) = x / 20
1.2799 = x / 20
x = 1.2799 * 20
<span><span><span>x = 25.598
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