You could get two different functions out of this:
<u>2x + 2y = 8</u>
1). <u> 'y' as a function of 'x'</u>
Subtract 2x from each side: 2y = -2x + 8
Divide each side by 2 : <em> y = -x + 4</em>
2). <u> 'x' as a function of 'y' :</u>
Subtract 2y from each side: 2x = -2y + 8
Divide each side by 2 : <em> x = -y + 4</em>
Those two functions look the same, but that's just because the original
equation given in the problem was so symmetrical. In general, they're
not the same function.
7y 4x and 2x they all are paired with a variable
22.5/(x-6) + 22.5/(x+6) = 9
multiply by x-6
=> (x-6)22.5/(x-6) + (x-6)22.5/(x+6) = 9(x-6)
=> 22.5 + (x-6)22.5/(x+6) = 9(x-6)
multiply by x+6
=> (x+6)22.5 + (x+6)(x-6)22.5/(x+6) = 9(x-6)(x+6)
=> (x+6)22.5 + (x-6)22.5 = 9(x-6)(x+6)
distribute
=> 22.5x+6(22.5) + 22.5x - 6(22.5) = 9(x^2 - 36)
=> 45x = 9x^2 - 9(36)
=> 0 = 9x^2 - 45x - 9(36)
divide by 9
=> 0 = x^2 - 5x - 36
=> 0 = x^2 - 5x - 36
=> 0 = (x - 9)(x + 4)
x=9 and -4
Answer:
B
Step-by-step explanation:
-2×4
=-8
a negative number multiplied by a positive number gives a negative number that is why it is -8 and not 8
