Evaluate 4(a2 + 2b) - 2b when a = 2 and b = –2.

Mathematics

2 answers:

Shkiper50 [21]4 years ago

8 0

4 ( (2)^2 + 2(-2) ) - 2(-2)
4 ( 4 - 4 ) + 4
0 + 4 = 4

goblinko [34]4 years ago

3 0

4(2² + 2(-2)) - 2(-2) = 4(4-4) + 4 = 4*0 + 4 = 4

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alexdok [17]

Observe attached picture.

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We can apply trigonometry rules to find height of flagpole.

From small triangle containing sign we can find tangens function:
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We see that these two equations have same left sides. This means that their right sides must also be same:
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