Answer:
x= 1/4 .....................
y=-1
the coordinates where the bridges must be built is
and
.
<u>Step-by-step explanation:</u>
Here we have , a road follows the shape of a parabola f(x)=3x2– 24x + 39. A road that follows the function g(x) = 3x – 15 must cross the stream at point A and then again at point B. Bridges must be built at those points.We need to find Identify the coordinates where the bridges must be built. Let's find out:
Basically we need to find values of x for which f(x) = g(x) :
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Value of g(x) at x = 3 : y=3x -15 = 3(3)-15 = -6
Value of g(x) at x = 6 : y=3x -15 = 3(6)-15 = 3
Therefore , the coordinates where the bridges must be built is
and
.
sum of two angles of triangle are equal to the exterior angle of triangle
A triangular prism Vol. = area (A) of the triangular base × height (h) of prism
A triangular pyramid V = A × 1/3 h
So since they have same base A and h, the V of the pyramid will be exactly 1/3 the V of the prism
The answer is A, not sure about the expression though. Sorry