Use substitution and substitute y into the other equation. One of the equations already gives you y in terms of x, so use that and substitute it into the other equation. y = 3x - 4
Plug into the other equation: -3y = -9x + 12
-3(3x-4) = -9x + 12
-9x + 12 = -9x + 12
This is an identity. So that means that any value of x makes this equation true. So B.
37÷6
=6.1666666667
- 0.1666666667
=6
First notice that the triangle with sides

and the triangle with sides

are similar. This is true because the angle between sides

in the smaller triangle is clearly

, while the angle between sides

in the larger triangle is clearly

. So the triangles are similar with sides

corresponding to

, respectively.
Now both triangles are

, which means there's a convenient ratio between its sides. If the length of the shortest leg is

, then the length of the longer leg is

and the hypotenuse has length

.
Since

is the shortest leg in the larger triangle, it follows that

, so
2a+1 + 3a+2 +5a-9 you would start by combining like terms
2a+3a+5a= 10a
1+2-9= -6
10a-6=94
then subtract 94-6=88
then divide 88 by 10= 8.8
a=8.8
21.50 x 25 = 537.50
10.75 x 5 = 53.75
537.50 + 53.75 = 591.25