1. If Cos(a)=Sin(52), what is the value of A?
A. 28
B. 38
C. 52
D. 128

2. If Sin B=7/9, what is Cos A?
Cos A=

What must be true about A and ?
A. a and b are complementary angles
B. mC. mD. a and b are suplementary angles

Part 1) Option B. 38°

Part 2) Cos A=7/9 ( A and B are complementary angles)

Step-by-step explanation:

Part 1)  If Cos(A)=Sin(52), what is the value of A?

we know that

If two angles are complementary, the cofunction identities state that the sine of one equals the cosine of the other and vice versa

so

If Cos(A)=Sin(52)

then

solve for A

Part 2) If Sin B=7/9, what is Cos A?

Cos A=____

In this problem we have that

Angle A and Angle B are complementary angles

so

Remember that

If two angles are complementary, the cofunction identities state that the sine of one equals the cosine of the other and vice versa

so

If Sin B=7/9

then

Cos A=7/9

25/4

step-by-step explanation:

call segment cd's length x. because dc and ab are parallel, angle acd and cab, so triangles adc and abc are similar and we can set up the equation x / ac = ac / ab, or x / 5 = 5 / 4 and x = 25/4.

14

step-by-step explanation: