The answer is 30 because
3/10 × 9/x = 30 .
Hope this helps
By the Pythagorean theorem,
.. x^2 +(x -46)^2 = (x +4)^2
.. 2x^2 -92x +2116 = x^2 +8x +16
.. x^2 -100x +2100 = 0
.. (x -50)^2 -400 = 0
.. x = 50 ±20 . . . . . only x=70 makes any sense in the problem
The height, x, of the tree is 70 meters.
For the first triangle x=70. 180-40 is 140. Divided that by 2 and you’d get 70.
The second triangle x=90. 180-45 is 135. 135-45 (the angle congruent to the other 45 degree angle) is 90.
The third triangle x=65. 180-50 is 130. 130 divided by two is 65.
Check all answers by adding all the angles of the triangle and make sure they equal 180
Apply the distributive property.
9
a
−
4
(
2
a
)
−
4
⋅
5
9
a
-
4
(
2
a
)
-
4
⋅
5
Multiply
2
2
by
−
4
-
4
.
9
a
−
8
a
−
4
⋅
5
9
a
-
8
a
-
4
⋅
5
Multiply
−
4
-
4
by
5
5
.
9
a
−
8
a
−
20
Subtract
8
a
8
a
from
9
a
9
a
.
a-20