Solve each system by elimination.
1) 10x + 7y=9 -4x - 7y=9

(3, -3)

Step-by-step explanation:

When asked to solve by elimination, you put them on top of one another, like you're going to add it.

10x + 7y = 9

-4x - 7y = 9

See that 7y? You can cancel those out because one is negative, and one is positive. So those are gone. You finish adding the rest of the numbers as usual and solve for x.

6x = 18

x = 3

Take x, and plug it into either equation to find y.

10(3) + 7y = 9

7y = -21

y = -3

(3, -3)

Hope this helped!

(2x + 16) + (x) = 180

step-by-step explanation:

given,

abcd is a quadrilateral inscribed in a circle

angle a is labeled x plus 16, (x + 16)

angle b is labeled x degrees, (x)

angle c is labeled 6x minus 4, (6x – 4)

angle d is labeled 2x plus 16, (2x + 16)

what equation can be used to solve for angle b?

we know that the sum of the opposite angles of a simple quadrilateral inscribed in a circle is 180 degrees.

angle b is opposite angle d

therefore, angle b + angle d = 180

(x) + (2x + 16) = 180 

same as (2x + 16) + (x) = 180