Substitution doesn't work for this, but elimination does.
-6x-8y=-20 +6( x+6y=-6)
-6x-8y=-20 + 6x+36y=-36
-6x and 6x cancel each other, add -8 and 36 to get 28, and -20 and -36 to get -56.
28y=-56
divide by 28 on both sides.
Y= -2
Then substitute y into one of the equations.
x+6(-2)=-6
x-12=-6
x=6
The ordered pair is (6,-2).
Answer:
Answer: Janet is 16, and David is 11.
Step-by-step explanation:
Let the ages be j and d.
j = d + 5
j + d = 27
Substitute d + 5 for j in the second equation.
d + 5 + d = 27
2d + 5 = 27
2d = 22
d = 11
Substitute 11 for d in the first equation.
j = d + 5
j = 11 + 5
j = 16
Answer: Janet is 16, and David is 11.
45+(45*.15)=
45+6.75=51.75
6.75 is the tip, 51.75 is the total bill
Tan(12) = 40/d
d = 40/tan(12)
d = 188.19m
Answer:
9 ft
Step-by-step explanation:
Let's begin with the formula for the volume of a square pyramid. If s is the base length, then the area of the base is s^2. The volume of the pyramid is then V = (1/3)(base area)(height). We know the volume and the base length (s), and want to find the height. Solving V = (1/3)(base area)(height)
for height, we get:
3V = (base area)(height), or
3V
---------------- = height
base area
Substituting 75 ft^3 for V and (5 ft)^2 for base area, we get:
3(75 ft^3) 9 ft
height = ------------------ = ----------------- = 9 ft
25 ft^2 1
