Answer:
x = - 9, x = 10
Step-by-step explanation:
Given
x² - x - 90 = 0
Consider the factors of the constant term (- 90) which sum to give the coefficient of the x- term (- 1)
The factors are - 10 and + 9, since
- 10 × 9 = - 90 and - 10 + 9 = - 1 , thus
(x - 10)(x + 9) = 0 ← in factored form
Equate each factor to zero and solve for x
x - 10 = 0 ⇒ x = 10
x + 9 = 0 ⇒ x = - 9
lesser x = - 9
greater x = 10
Refer to c^2=a^2+b^2 (^2 means squared)
C is the hypotenuse and will be the longest measure
So 15^2= 9^2+12^2
225=225
If both sides are equal then the triangle is a right triangle, if the hypotenuse (or c) is lower or higher than you can determine whether it’s obtuse or acute
It would be a right triangle
Answer:
cos 4u = co^s2 2u - sin^2 2u
Step-by-step explanation:
cos 4u = co^s2 2u - sin^2 2u
Let 4u = 2x
cos 2x = cos^2 x - sin^ 2 x
cos (x+x) = cos^2 x - sin^ 2 x
Using cos(x+y) = cos(x)cos(y) -sin(x)sin(y)
cos(x) cos(x)- sin(x) sin (x)= cos^2 x - sin^ 2 x
cos^2 (x) -sin^2 (x) =cos^2 x - sin^ 2 x
Since this is true
cos 2x = cos^2 x - sin^ 2 x
This is true
Substituting 4u back for 2x
cos 4u = co^s2 2u - sin^2 2u
This is true
Answer:
84
Step-by-step explanation:
I don't really know how to explain it but I'll try my best
Visualize line AB extending past point A (like it does at point B)
You'll see that 180 ( line AB ) minus 129 is 51
Angle 51 is vertical to the other angle inside the triangle that is unnamed.
Now you have 2 angles.
180-45-51=84
