(xy)² - x + y
= (2*4)² - 2 + 4
= 8² + 2
= 64 + 2
= 66
(9x - 3y)²
= (9*2 - 3*4)²
= (18 - 12)²
= 6²
= 36
Answer:
look at attached image, hope this helps! :)
Tan 60 = GI / HG
Root 3 = 11/HG
HG = 11/root 3
HG = 6.3cm
Sin 60 = 11/ HI
Root 3 / 2 = 11/HI
Root 3 x HI = 11 x 2
HI = 22/root 3
HI = 12.7cm
Regards,
ArmyCee:)
A^2 + b^2 = c^2
x^2 + 8^2 = 20^2
x^2 + 64 = 400
x^2 = 336
x = 4sqrt(21), or ~=~ 18.3303028