Answer:
B. 3/2
Step-by-step explanation:
The slopes of perpendicular lines are negative reciprocals
The negative reciprocals of -2/3
is 3/2
Answer:
a
Step-by-step explanation:
You don't need the apothem if the side length is known, the area can be expressed as:
A(n,s)=ns^2/(4tan(180/n)), n=number of sides and s=side length so
A(7,28)=(7*28^2)/(4tan(180/7))
A≈2848.987 ft^2
A≈2849 ft^2 (to the nearest tenth of a square foot)
We have 60 gallons of 20% antifreeze.
How much 70% antifreeze do we add to get 60% antifreeze?
We'll make "x" the gallons of 70% we must add.
.20 * 60 + .70 x = .60 * (60 + x)
12 + .70x = 36 + .60x
.10x = 24
x = 240 gallons of 70% antifreeze.
Source
1728.com/mixture.htm (see example B)