30 points!! Find the value of x. Show yours steps.

x=10

Step-by-step explanation:

Supplementary angles 142+2(x+9)=180

Subtract 142 frrom both sides

2(x+9)=38

now distribute

2x+18=38

subtract again

2x=20

Divide both sides by 2

x=10

step-by-step explanation:

the multiplicative inverse of a fraction a/b is b/a. for the multiplicative inverse of a real number, divide 1 by the number. for example, the reciprocal of 5 is one fifth 1/5 or 0.2, and the reciprocal of 0.25 is 1 divided by 0.25, or 4.

c.

step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.