Answer:
b=320; slope=-30
Step-by-step explanation:
if you look along the y-axis find the spot that the line intercepts and then that's b
now for the slope
find two points on the line, i chose(8 , 120) and (4 , 240)
use the slope formula: y2-y1 over x2-x1
240-120=120 and 4-8= -4
so the slope is 120/-4 and that can be simplified to 30/-1 or -30
12:7
because you add 7 and 5 and then there is the 7 for the book weight
Focus on triangles DFC and DFE:
- They are both right triangles because DF is perpendicular to EC
So, the two triangles are congruent. It follows that CF=FE, and in particular

And since x=3, the length of EF is

Take the 4 out to get 4(x^2-12.5)