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
So this is our table:
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x-values | a b c d e f |
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y-values | g h i j k l |
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You can know that the values in the table are proportional if:
Hope that helps :)
Answer: x= log18 (10) +1/2
x= 1.29664
Good luck !
Answer:
4.1, 2.21, 0.25,0.042
Step-by-step explanation:
you have to add a 0 onto the first one because it will bring it to be equal to most of the others
Answer:
i dont know
Step-by-step explanation:
