Does anyone know the answer for 7 and 8?

7) A    8) C

Step-by-step explanation:

number 7 tells us that y=x+1

so we just basically plug it in

2x+3(x+1)=4   A

to eliminate x's in number 8, we have to multiply one of the equations by -1

let's multiply the second one

4x+3y=6

4x ·-1-y·1=2·-1

4x+3y=6

-4x+y=-2

x's eliminate

4y=4, meaning that the answer is C

definition: a circle is the  set of all points in a plane that are equidistant  from a given  point  called the center of the circle. we use the symbol ⊙ to represent a circle. the a line segment from the center of the circle to  any point  on the circle is a radius of the circle.

step-by-step explanation:

i googled it and this is what i got i don't know how it is. sorry.

answer is because 4×10=40

and 98×4= is 392

40,392