It went from 10 to -2, so you need to find the difference. The way you'd do this is: 10 - (-2). Do you know how to subtract a negative number from a positive number?
I don't know how much money
Slope-intercept form:
y = mx + b "m" is the slope
First i would isolate the "y" in the equation.
2x + y = 4 Subtract 2x on both sides
2x - 2x + y = 4 - 2x
y = 4 - 2x or y = -2x + 4
The given line's slope is -2.
For lines to be perpendicular, their slopes have to be the opposite/negative reciprocals (flipped sign and number)
For example:
slope is 2
perpendicular line's slope is -1/2
slope is -2/3
perpendicular line's slope is 3/2
The given line's slope is -2, so the perpendicular line's slope is 1/2.
The 3rd option is your answer
After manipulating above equation we get, 2x^2 - 7x - 8= 0. Discriminant= b^2 - 4ac = (-7)^2 - 4(2)(-8) = 113>0. So there are 2 real roots :)
