So here's how to do it,
slope intercept form is y=mx+b
m is the slope, b is the y- intercept, X is your unknown variable.
you need to solve to get y by its self to get your slope.
for perpendicular lines flip the slope
ex 1, smy=2x+6 --- slope of a perpendicular line will be 1/2
ex 2, y=3/2+8 ---8 perpendicular lien would have a slope of 2/3
parallel lines have the same slope so any equation with with the same slope will be parallel if it has the same degree.
ex. y=2x+14 is parallel to y= 2x+56
slope can be found using the following formula if you have two sets of points on the same line
m= y2-y1 ÷ X2 - X1
The answer to the equation is X = 7
In linear models there is a constant additve rate of change. For example, in the equation y = mx + b, m is the constanta additivie rate of change.
In exponential models there is a constant multiplicative rate of change.
The function of the graph seems of the exponential type, so we can expect a constant multiplicative exponential rate.
We can test that using several pair of points.
The multiplicative rate of change is calcualted in this way:
[f(a) / f(b) ] / (a - b)
Use the points given in the graph: (2, 12.5) , (1, 5) , (0, 2) , (-1, 0.8)
[12.5 / 5] / (2 - 1) = 2.5
[5 / 2] / (1 - 0) = 2.5
[2 / 0.8] / (0 - (-1) ) = 2.5
Then, do doubt, the answer is 2.5
The answers is D 21,000because you have to do 60,000x.35=21,000