Answer:
7 feet long
Step-by-step explanation:
This set up will give a right angle triangle where;
Length of the ladder is the hypotenuse = x
The distance of the ladder to the house is the adjacent = 3 feet
Angle of elevation theta = 72 degrees
Using the CAH in trigonometry identity;
cos theta = adjacent/hypotenuse
cos 72 = 3/hyp
hyp = 3/cos72
hyp = 3/0.4258
hyp = 7.05 feet
Hence the ladder is approximately 7 feet long
3.15 /7 = 0.45
3.20/8 = 0.40
4.10/10 = 0.41
4.80/16 = 0.3
Answer is 1. 7 stamps worth 3.15
Remember you can do anyting to an equation as long as ou do it to both sides
-6x+4=-50
minus 4 both sides
-6x=-54
divide both sides by -6
x=9
5x+6=-44
minus 6 both sides
5x=-50
divide both sides by 5
x=-10
-3(7+6x)=-201
normally you would distribute (that works) but it's easier to divide both sides by -3
7+6x=67
minus 7 both sides
6x=60
divide by 6 both sides
x=10
Got a calculator? all you do for #1 and #2 is multiply the two numbers and that is the value for x.
These problems are cross multiplication.
For the next two:
.25x = 6
divide both sides by .25
x = 24
NEXT ONE:
.49x = 12
divide both sides by .49
x = 24.48