The answer is C it’s vertex is at (2,4) because a quadratic formula is suppose to look like y= a ( x - h )^2 + k and the vertex is (h,k) when you look back at Your question h=-2 and but Bc of the formula then it’ll be h=2 and then k=4 and that’s how you get the vertex from a quadratic formula. Hope this helps :)
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Answer:
a) ∆ABC ~ ∆EDC by AA similarity
b) ED/AB = 3/4
c) 15 cm
Step-by-step explanation:
a) Two angles in each triangle are the same, so the AA similarity postulate can be used to declare the ∆ABC ~ ∆EDC. (Each triangle includes a right angle and angle C.)
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b) Corresponding sides are ED/AB, DC/BC, EC/AC. The ratio of corresponding sides is ED/BC = (12 cm)/(16 cm) = 3/4.
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c) Using the ratios identified above, we have ...
DC/BC = 3/4 = x/(20 cm)
x = 3/4(20 cm)
x = 15 cm
