Use the equation .8x + x = 252
x is the number, and .8 is the decimal equivalent of 80%.
1.8x = 252
x = 140
The answer is 2 I believe
The slope of any function is its first derivative.
If f(x)=x^2, then f'(x)= 2x .
At x=5, slope = f'(x) = 2(5) = <em>10</em> .
The cost depend on the number pencils, so the cost is the y and # of pencils is the x
Same as for question 7
To graph, the length depend on the time, so length is y, time is x
6. Linear
7. Not