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If a=5x-2 and b=5x-22 , what is the value of x ?

If a=5x-2 and b=5x-22 , what is the value of x ?-example-1
User Howard Shane
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1 Answer

17 votes
17 votes

Trigonometry

We are given the following condition:

sin (a) = cos (b)

Since both angles are acute, the following relationship must apply:

a = 90° - b

Both angles must be complementary

Substituting the values for each angle:

a = 5x - 2

b = 5x - 22

We have:

5x - 2 = 90 - (5x - 22)

Removing brackets:

5x - 2 = 90 - 5x + 22

Adding 5x:

5x - 2 + 5x = 90 + 22

Adding 2:

5x + 5x = 90 + 22 + 2

Simplifying:

10x = 114

Dividing by 10:

x = 114/10

x = 11.4

Correct choice: C)

User Sawe
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