Answer:

Step-by-step explanation:
Based off of what we do know, if we can find length DB we can use the pythagorous theorem (I will be assigning the variable z)

First equation is for triangle ABD
Second is for BCD
And the last one is for ACD
Substitute
and 

As discovered before

Answer:
2100
Step-by-step explanation:
5/210=50/x
x= 50*210 / 5
x= 2100
7. y=-3/2x+8 (3rd answer choice)
substitute
-4=-3/2(8)+b
-4=-24/2 +b
-4=-12+b
+12 both sides
8=b
so equation would be...
y=-3/2x+8 (3rd answer choice)
8. y=-5x-17 (2nd answer choice)
substitute
-2=-5(-3)+b
-2=15+b
-15 both sides
-17=b
so the equation would be...
y=-5x-17 (2nd answer choice)
check your work by substituting each (x,y) value into the final equations if you want. hope this helps :))
1 does not represent a function