Answer:
see explanation
Step-by-step explanation:
A rectangle is is a type of parallelogram with four right angles.
16x²-49=
(4x)²-7²=
(4x-7)(4x+7)
Here I have used the expression:
a²-b²=(a-b)(a+b)
Answer:
y = 42°
Step-by-step explanation:
The third vertex in the triangle with y is adjacent to a right angle, thus is right.
The sum of the 3 angles in a triangle = 180°, then
y = 180° - (90 + 48)° = 180° - 138° = 42°