Answer:
36
Step-by-step explanation:
To complete the square:
we take the coefficient ox "x" (which in this problem is -20)
we divide it by 2
square that number
then add it to both sides of the equation
-20 / 2 = -10
-10^2 = 100
then we add 100 to both sides of the equation:
x^2 -20x
x^2 -20x +100 = 100
******************************************************
To get the roots of the equation, we take the square root of both sides:
(x -10) * (x-10) = 10
(x-10) = square root (10)
x-10 =
<span>
<span>
<span>
3.1622776602
</span>
</span>
</span>
x1 =
<span>
<span>
<span>
13.1622776602
</span>
and don't forget that square root of 10 also equals </span></span><span><span><span> -3.1622776602
</span>
</span>
</span>
x2 = 10
-<span>
<span>
<span>
3.1622776602
x2 = </span></span></span>
<span>
<span>
<span>
6.8377223398
</span>
</span>
</span>
Answer:
y = 1/2x - 9/2
Step-by-step explanation:
5, 10 ,15
divide each by 5
1,2, 3
so the ratios should be 1,2,3
Metal 1 : divide by 150
1,2,4
Metal 2 divide by 130
1,2,3
Metal 3 divide by 310
1,2,3
Metal 4 divide by 140
1,2,3
Metal 1 is not proportional
Choice A