Well first you have to simplify the denominators with x, by multiplying the denominator on the left times the top and bottom of the middle, and vice versa to get 10x/(4x^2-4x)-9(2x-2)/(4x^2-4x)=-1/4 and then you combine the fractions on the left to get 2(9-4x)/(4x^2-4x)=-1/4 and then you cross multiply the fractions to get 8(9-4x)=-4x^2+4x and then simplify to get 72-32x=-4x^2+4x and then 4x^2-36x+72=0 which then we can turn into 4(x-6)(x-3)=0 so x is 6 and 3
We can use two different ways to solve this equation:
Because the board is 25 off, we can multiply the price and subtract the result:
30 - 0.25(30) = 30 - 7.5 = $22.50
We can also solve by multiplying the total price by 0.75
(1 - 0.25)(30) = 0.75(30) = $22.50
The sales price is $22.50
Answer is choice DThis is the only answer choice with a negative slope, so we don't even need to look at the point really. Though if you wanted, you can confirm that the point (1,-3) is on the diagonal line. This point is shown in red in the attached image.
To find that the slope is -6/5, you pick two points on the diagonal line and use the slope formula. Two points you can use are (1,-3) and (-4,3).
The slope formula is m = (y2-y1)/(x2-x1)
Note: The negative slope is because we move downhill as we move from left to right along the diagonal line.
volume = 4/3 x PI x r^3
r = 10/2 =5
V = 4/3 x 3.14 x 5^3 = 523.333
523.3 cubic inches
If Yoshi has 8 per pack and used 7 he would have 32 markers in all and bought 3 packs and had an extra marker