X^2-6x+9=0 has only one solution
Hope this helps
Cos(A-B) = cosAcosB + sinAsinB
<span>
cos(</span>π/2 - θ) = cos(π/2)cosθ + sin(π/2)sinθ
π/2 = 90°
cos(π/2) = cos90° = 0. sin(π/2) = sin90° = 1
cos(π/2 - θ) = cos(π/2)cosθ + sin(π/2)sin<span>θ
</span>
= 0*cosθ + 1*sin<span>θ = </span>sin<span>θ
Therefore </span>cos(π/2 - θ) = sin<span>θ
QED </span>
Answer:

Step-by-step explanation:
The formula that is used to calculate the area of a rectangle is:

Where "l" is the lenght and "w" is the width.
You know that the area of that rectangle is:

And, according to the exercise, its lenght is 7 more than its width; then:

Then, you can make the corresponding substitution into the formula
:

Simplify:

Factor the equation. Find two numbers whose sum is 7 and whose product is -744. These are 31 and -24.
Then, you get:

The width of the rectangle is the positive value:

Then, the lenght is:

Divide the number & Multiply
Answer:
(4) 29, 33, 37
(6) 53, 59, 65
(5) -16, -20, -24
Step-by-step explanation: