Question

Emily designed a robot that could climb down steps. She drew a graph to show the results from a test of her new robot. The graph shows the number of steps remaining over time.

What is the equation that represents Emily’s situation?

y=110x+15y=110x+15

y=−10x+150y=−10x+150

y = 10x + 150

y=−110x+15y=−110x+15
First quadrant grid, x-axis numbered 0 to 150 and labeled Seconds, y-axis numbered 0 to 19 and labeled Steps. A line with negative slope intersects the y-axis at 15 and the x-axis at 150.

Answer 1

So youre a given two points. The points (0,15) and (150,0). First solve the slope of the graph

M = (y1 – y2) / (x1 – x2)

M= (15 – 0) / ( 0 – 150)

M = - 0.1

Using point (15,0)

15 = -0.1(0) + b

15 = b

So y = mx + b

Y = -0.1x + 15