Asap will mark brainliest
a. what is the value of x?

b. what is the value of y?

c. what is the value of z?

x = 81 degrees (The sum of a triangle's angles must be 180 degrees. 48 + 51 = 99, and 180 - 99 = 81)

y = 99 degrees (Y and X are on a supplementary angle. Like a triangle, a supplementary angle's angles must add up to 180 degrees. 180 - 81 = 99)

z = 129 degrees (Z and the 51 degree angle are also on a vertical angle. 180 - 51 = 129)

Hope this helps!

Double the "sum of 11.9 and a number"

Let a number = x.

Note that sum of 11.9 and a number (x) is first

Also, note that double means to "multiply by 2)

2(11.9 + x) is your expression

hope this helps