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For the right triangle shown, a =4 and b =5. Which expression represents the value of c?

A right triangle has sides of length \( 2\sqrt{2} \) ,\( 6\surd 2 \), and \( \surd 80 \)units. What is the area of the triangle, in square units?

what is the value of cos A in the triangle shown?

Triangle ABC is similar to triangle DEF, where angle A corresponds to angle D and angles C and F are right angles. The length of \( AB \) is 2.8 times the length of \( DE \) . If \( tanA=\frac{20}{21} \) , what is the value of sin D?

Point F lies on a unit circle in the xy-plane and has coordinates (1, 0). Point G is the center of the circle and has coordinates (0, 0). Point H also lies on the circle and has coordinates (-1, y), where y is a constant. Which of the following could be the positive measure of angle FGH, in radians?

For two acute angles, ∠\( Q \) and ∠\( R \), cos(\( Q \)) = sin(\( R \)). The measures, in degrees, of ∠\( Q \) and ∠\( R \) are x +61 and 4x + 4, respectively. What is the value of x?

The measure of angle F is \( \frac{7π}{4} \) radians. What is the value of cos(F) ?

For two acute angles,∠Q and ∠R, cosQ = sinR. The measures, in degrees, of ∠Q and ∠R are x + 27 and 4x ＋ 3, respectively. What is the value of x ?

The measure of angle D is \( \frac{5π}{4} \) radians. What is the value of sin(D)?

ln triangle ABC, the measure of angle C is 90 degrees. The cosine of angle A is \( \frac{60}{61} \) . what is the sine of angle B?

Right triangles ABC and DEF shown above are similar, where A corresponds to D and B corresponds to E. If tan(A) = \( \frac{15}{25} \), what is tan(F) ?

Triangle ABC is similar to triangle DEF, where angle A corresponds to angle D and angles C and F are right angle. The length of AB is 2.4 times the length of DE. If tan A=21/20, what is the value of sin D?