The third choice, 4x²+18x+0.25=0, is correct.
The frame will have the same thickness on both sides of the mirror. Therefore we add 5+x+x to get the total length, and we have 4+x+x to get the total width.
The area is found by multiplying the total width and total length:
A=(5+x+x)(4+x+x)
A=(5+2x)(4+2x)
Multiplying the binomials, we have:
A=5*4+5*2x+2x*4+2x*2x
A=20+10x+8x+4x²
A=20+18x+4x²
We know that the area is 19.75:
19.75=20+18x+4x²
We need quadratics set equal to 0, so subtract 19.75 from each side:
19.75-19.75 = 20+18x+4x²-19.75
0=0.25+18x+4x²
In standard form, it will be:
4x²+18x+0.25=0
Just finished the test :D. The answer would be -31 1/3
HOPE THIS HELPS :D
Answer:
number of people=56320
Step-by-step explanation:
area of street=2×1760×3×6=63360 cm²
number of people={63360÷(3× 3)}× 8=7040× 9=56320
Answer:
(3×3)+2=11
$11
Step-by-step explanation:
