Answer:
x² + y² = 85
Step-by-step explanation:
Using the expansion
(x - y)² = x² + y² - 2xy , then
x² + y² - 2xy = (x - y)² ( add 2xy to both sides )
x² + y² = (x - y)² + 2xy ← substitute given values
= 9² + 2(2)
= 81 + 4
= 85
The two angles shown are supplementary angles, meaning that there sum equals 180. Knowing this you can set up an equation and solve for h...
3h + 18 + 15h = 180
Combine like terms
18h + 18 = 180
Subtract 18 to both sides
18h + (18 -18) = 180 - 18
18h = 162
Isolate h by dividing 18 to both sides
18h/18 = 162 /18
h = 9
Hope this helped!
Answer:
7/9
Step-by-step explanation:
7/9
Take L.H.S sin2A+sin2B/sin2A-sin2B
= sin2A+sin2B/sin2A-sin2B
Put
[sinC+sinD = 2sin(C+D)/2cos(C-D)/2]
[sinC-sinD = 2cos(C+D)/2.sin(C-D)/2]
= 2 sin(2A+2B)/2 cos(2A-2B)/2 / 2 cos(2A+2B) sin(2A-2B)
= sin(A+B).cos(A-B)/cos(A+B).sin(A-B)
= sin(A+B)/cos(A+B) . cos(A-B)/sin(A-B)
= tan(A+B).cot(A-B)
= tan(A+B).1/tan(A-B)
= tan(A+B)/tan(A-B)
∴ Hence we proved sin2A+sin2B/sin2A-sin2B=tan(A+B)/tan(A-B)