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Which equation correctly uses the value of x to represent the cosine of angle A? cos(53o) = StartFraction 4 Over x EndFraction cos(53o) = StartFraction y Over 5 EndFraction cos(53o) = StartFraction x Over 4 EndFraction cos(53o) = StartFraction 5 Over y EndFraction

2 Answers

3 votes

Answer:

simple answer B

Explanation:

User Skeolan
by
4.2k points
1 vote

Here is the full question:

Triangle ABC is a right-triangle and sin(53o) = StartFraction 4 Over x EndFraction. Solve for x & round to the nearest whole number.

Triangle A B C is shown. Angle A C B is a right angle and angle B A C is 53 degrees. The length of B C is 4 centimeters, the length of A C is y, and the length of hypotenuse A B is x.

Which equation correctly use the value of x to represents the cosine of angle A?

cos(53o) = StartFraction 4 Over x EndFraction cos(53o) = StartFraction y Over 5 EndFraction cos(53o) = StartFraction x Over 4 EndFraction cos(53o) = StartFraction 5 Over y EndFraction

Answer:

cos(53°) = StartFraction y Over 5 EndFraction

Explanation:

From the information above:

The sketch of the triangle is drawn and attached in the diagram below.

To find x using the sine rule,

We know that:


Sin \theta = (opposite)/(hypothenuse)


Sin (53^0) = (4)/(x)

Making x the subject of the formula:


x = (4)/(Sin \ 53^0)


x = (4)/(0.7986)


x \simeq 5

Now, the equation that correctly uses the value of x can be determined by finding the cosine of ∠ A.

Recall that:


Cos \theta = (adjacent)/(hypothenuse)


Cos \ 53^0 = (y)/(x)

where; x = 5


Cos \ 53^0 = (y)/(5)

Thus, the equation that correctly uses the value of x to represent the cosine of angle A is:

cos(53°) = StartFraction y Over 5 EndFraction

Which equation correctly uses the value of x to represent the cosine of angle A? cos-example-1
User Michael Granger
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4.2k points