(f ◦ g)(x) = f(g(x))
substitute x = g(x) = 5 - 3x into f(x)
f(g(x)) = f(5 - 3x) = 7(5 - 3x) - 4 = 35 - 21x - 4 = 31 - 21x
(g ◦ f)(x) = g(f(x))
substitute x = f(x) into g(x)
g(f(x)) = 5 - 3(7x - 4) = 5 - 21x +12 = 17 - 21x
Plane UVWX and plane QRST
Answer:
60 I guess,,,,,,,,,,,.,,,.
Draw a rectangle. If the length is 3 inches longer than its width, we can write the width as "w" and the length as the width + 3
Area is (width)(Length) = (width)(width+3)
W
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| |
| | L = w+3
| |
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A = (w+3)(w)
A = w2 + 3w = 108.
(Problem states that area is 108 sq in)
Need to solve this quadratic equation
w2 + 3y - 108 = 0
Factor:
(w - 9) (w + 12) = 0
So
w - 9 = 0. or. w + 12 = 0
Solve these and get
w = 9. or. w = -12
Only one that makes sense in real life is the poitive one.
So the dimensions are
Width = 9 inches
Length = 12 inches