For these kinds of expressions use FOIL (first, outside, inside, last).
-2x • 9x = -18x^2
-2x • -3y = 6xy
8y • 9x = 72 xy
8y • -3y = -24y^2
Now combine them all:
-18x^2 + 78xy - 24y^2
We are given the height of Joe which is 1.6 meters, the length of his shadow is 2 meters when he stands 3 meters from the base of the floodlight.
First, we have to illustrate the problem. Then we can observe two right triangles formed, one is using Joe and the length of the shadow, the other is the floodlight and the sum of the distance from the base plus the length of the shadow. To determine the height of the floodlight, use ratio and proportion:
1.6 / 2 = x / (2 +3)
where x is the height of the flood light
solve for x, x = 4. Therefore, the height of the floodlight is 4 meters.
Answer:
Step-by-step explanation:
Answer:
x
=
3
10
+
1
10
29
or
x
=
3
10
+
−
1
10
29
