5.75a + 6.5c = 53.25
a + c = 9
c = 9 - a
5.75a + 58.5 - 6.5a = 53.25
5.25 = 0.75a
a = 7
7 + c = 9
c = 2
she bought 7 apple pies
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*You could use a calculator
50 times 50 times 50 times 20 equals <span>2500000</span>
Your answer is <em>2500000</em>
Notice that 6 is a factor of all three coefficients and thus can be factored out:
6x^2 -42x-54 => 6(x^2 - 7x - 9). x^2 - 7x - 9 does not factor so easily. Remembering that obtaining roots of a quadratic makes it easy to write out the corresponding factors, let's apply the quadratic formula to x^2 - 7x - 9:
a=1, b = -7, c = -9. Then the discriminant is b^2 - 4ac, or (-7)^2 - 4(1)(-9), or 85.
Thus, the roots are:
7 plus or minus √85 7 plus or minus 9.220
x = -------------------------------- = ------------------------------------
2 2
Let's call these roots "a" and "b." Then the factors of the quadratic x^2 - 7x - 9 are (x-a) and (x-b), or, in this case, (x-8.11) and (x+1.11).
The original quadratic has three factors: 6, (x-8.11) and (x+1.11).
Step-by-step explanation:
to find the area of the prism the given formula is,
perimeter× height
