22% of 400
88 is your answer
Answer:
GF = 25.2
Step-by-step explanation:
GF/BC = (AD-FE)/AD
GF = BC(AD-FE)/AD = 36(20-6)/20
GF = 25.2
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The ratio of GF to BC is the ratio of DE to DC. The ratio of FE to AD is the ratio of CE to CD. That is ...
GF/BC = (CD-CE)/CD = 1 - FE/AD = (AD -FE)/AD . . . . . as above
Rearrange the equation by writing
x² + x - 90 = 0
x² + x = 90
x² + x + 1/4 = 90 + 1/4
Recall that (a + b)² = a² + 2ab + b². Then
x² + 2 • x/2 + (1/2)² = 361/4
(x + 1/2)² = 361/4
x + 1/2 = ± √(361/4)
x = -1/2 ± 19/2
x = 9 or x = -10
Strategy A because it a quick way to find the answer