Solve the system by substitution y=10x y=-3x-104

 (-8, -80)

Step-by-step explanation:

y = 10x

y = -3x - 104

Substitute "y" with "10x" into the second equation, then solve for x:

10x = -3x - 104

13x = -104         added 3x to both sides

  x = -8             divided both sides by 13

Next, substitute -8 for x into the first equation to solve for y:

y = 10(-8)

  = -80

step-by-step explanation:

the shape,the size and the distance

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional