Purr fbfbfbffjhfbfbfbfbfbfbf
Answer:
No mistake
Step-by-step explanation:
2x + y = 5
x - 2y = 10
y = 5 - 2x
x - 2(5 - 2x) = 10
x - 10 + 4x = 10
5x - 10 = 10
5x = 20
x = 4
2(4) + y = 5
y = -3
She made no mistake
You can check by plugging in x = 4 and y = -3 into the original equations . They fit exactly.
Hi friend,
This is a perfect square trinomial.
It can be recognised because it is of the form:
a^2−2ab+b^2=(a−b)^2
with a=3x and b=4
9x2−24x+16=(3x)2−(2⋅(3x)⋅4)+42
=(3x−4)2