This is parallelogram so
8=2x
X=4
Or
3x=12
So again we will find x=4
Answer:
Student B is correct
Student A failed to distribute -4 and -6 when opening the brackets in the first step
Step-by-step explanation:
The solution Student A gave was:
2x - 4(3x + 6) = -6(2x + 1) - 4
2x - 12x + 6 = -12x + 1 - 4
-10x + 6 = -12x - 3
2x = -9
x = -4 _1 2 ( -4 1/2)
The solution Student B gave was:
2x - 4(3x + 6) = -6(2x + 1) - 4
2x - 12x - 24 = -12x - 6 - 4
-10x - 24 = -12x - 10
2x = 14
x = 7
Student B is correct.
Explanation of the error:
Student A failed to distribute -4 and -6 when opening the brackets in the first step.
That is,
2x - 4(3x + 6) = -6(2x + 1) - 4
To open this bracket, we will distribute, -4 and -6 so that we get
2x (-4 × 3x) + (-4 × +6) = (-6×2x) + (-6 × +1) - 4
Then we will get
2x -12x -24 = -12x -6 -4
Adding the like terms
-10x - 24 = -12x - 10
Collecting like terms
-10x + 12x = -10 + 24
∴ 2x = 14
x = 14 / 2
Hence,
x = 7
Assuming that the triangles are congruent, you can just look at the parts on each triangle to find the parts on the other triangle. The answers are yes, yes, and no. The triangles are obviously not drawn to scale, so just remember to never rely on it being so.
You can you 72 which would make 2/8 18/72 and 3/9 24/72 which makes the sum 42/72.