The interior angles of a parallelogram will always equal 360. The interior angles of a triangle are 180 if it is a equilateral triangle then the angles are 60 degrees each. You know 2 sides of parallelogram. The 100 degree and 90 degree. You can find the one opposing the x because it’s on a straight line and a straight line is 180 degrees if a triangle is 60 degree angle then the opposing angle to complete the straight line must be 180-60 so you get 120. You now know 3 sides. 120, 90 and 100
They should add up to be 360 so you can set up an equation like so
120+90+100+x=360
And x = 50
Answer:
The 3 possible values of x are;
6, 4 and 2
Step-by-step explanation:
If the triangle is isosceles, then two of the sides must be equal
So we equate the sides, 2 at a time to get the different values of x
3x + 4 = 2x + 10
3x-2x = 10-4
x = 6
3x + 4 = x + 12
3x-x = 12-4
2x = 8
x = 8/2 = 4
2x + 10 = x + 12
2x - x = 12-10
x = 2
Option B:

Solution:
Given sound level = 120 decibel
To find the intensity of a fire alarm:

where 
Step 1: First divide the decibel level by 10.
120 ÷ 10 = 12
Step 2: Use that value in the exponent of the ratio with base 10.

Step 3: Use that power of twelve to find the intensity in Watts per square meter.


Now, do the cross multiplication,




Option B is the correct answer.
Hence
.
Answer:
I think the answer is Step 2, 12x − 16 = 16 + 4x
plz mark me as brainliest if i was right :)