Answer:
Van: 36 mph.
Plane: 102 mph.
Step-by-step explanation:
x = speed of van
y = common time value
(3x - 6) * y = 204 // plane
x * y = 72 // van
3xy - 6y = 204 // plane simplified
We can now substitute 72 for xy in the equation above.
3*72 - 6y = 204 --> 216 - 6y = 204
We now subtract 216 from both sides.
-6y = -12
We now divide both sides by -1 to get rid of the negative sign & then divide both sides by 6 to simplify.
y = 2
If x*y = 72, then x = 72/y = 72/2 = 36.
Thus, the speed of the van is 36 mph.
We can find the speed of the plane by using the equation from earlier, 3x - 6.
3x - 6 = 3*36 - 6 = 108 - 6 = 102.
Answer:
Step-by-step explanation:
From the way it is written, the is outside the square root. I will rewrite it as:
Multiply denominator and numerator by 3
Factor
Divide denominator and numerator by
Let's rewrite it again
It is already in the form
Expanding the perfect square, we have
Factor
Therefore,
For the 2nd picture, c. 26/7
Answer:
A) 684 in^2
Step-by-step explanation:
Since it needs to be painted all around the box we have to find the surface area of the box
The surface area of cuboid is
=2lw+2lh+2hw (l: length, w: width, h: height)
=2×15×12+2×6×15+2×6×12
= 684 in^2