Let
and
. Then


and


The expression under the square root can be rewritten as

Recall that

so that

and assuming
and
, we end up with

so that

as required.
Trapezoid Area = (Bases / 2) * Height
20 cm² = 5 * Height
Height = 4 cm
The increase is D: 50% because the 1 in the parentheses stands for the 20 that was already there, with the .5 being the amount that’s actually being increased. 0.5 translates to 50%, so the answer is D.
Answer: for 4 The 24 balloons cost are $40 and 9 balloons are $1.67
Step-by-step explanation: