Answer:
a) 7x^2 + 5x
Step-by-step explanation:
(9x^2 + 8x) – (2x^2 + 3x)
Distribute the minus sign
(9x^2 + 8x) – 2x^2 - 3x
Line them up vertically
(9x^2 + 8x)
– 2x^2 - 3x
-------------------
7x^2 +5x
This question uses trig
sin(55) = height/195
Therefore, height = 195sin(55) meters (just plug in calculator)
Answer:
x=13,y=0
Step-by-step explanation:
We are given a system of equations

For equation 1,square all terms to reduce it
√x²+√y²=169
x+y=13
Make x the subject as required by the question to use substitution method
x=13-y
Plug x=13-y into eqn 2
3(13-y)+2y=39
39-3y+2y=39
39-y=39
y=39-39=0
Plug y=0 into equation 1
x+0=13
x=0
Answer:
B
Step-by-step explanation:
using the tangent ratio on the triangle on the right and the exact value
tan60° =
, then letting the altitude be h
tan60° =
=
=
( multiply both sides by h )
11
= h ×
( divide both sides by
)
11
= h
using the sine ratio in the triangle on the left and the exact value
sin45° =
, then
sin45° =
=
=
=
( cross- multiply )
× x = 22
( divide both sides by
)
x = 22