Answer:
A pair of vertically opposite angles are always equal to each other.
As you can see there are two triangles but it can be done calculating just for one. First we must understand how formula for area of triangle works.

Where
represents base (hypotenuse) and
as height of the triangle.
We know that:

Using this data we fill the formula.

Hope this helps.
r3t40
A trapezoid with legs MN = FD is an isosceles trapezoid.
An isosceles trapezoid has diagonals that are congruent, therefore: MF = ND.
A quadrilateral with diagonals congruent and perpendicular is a square.
In a square, the height coincides with the side.
The area of a square is given by A = s²
Therefore, the area of MNFD is h²
A) I would make the positive integer x and then form an equation.
x + 30 = x^2 - 12
x + 42 = x^2
0 = x^2 - x - 42 this can be factorised
(x - 7) ( x + 6) Therefore x = 7 or x = -6
Since the question asks for a positive integer the answer is 7.
B) two positive numbers x and y.
X - y = 3
x^2 + y^2 = 117
Use these simultaneous equations to figure out each number.
Rearrange the first equation
x = y + 3
Then substitute it into the second equation.
(y+3)^2 + y^2 = 117
y^2 + 6y + 9 + y^2 = 117
2y^2 + 6y - 108 = 0
then factorise this.
(2y - 12) (y + 9)
This means that y = 6 or y = -9 but it’s 6 because that’s the only positive number.
Use y to find x
x = y + 3
x = 6 + 3
x = 9
So the answers are x = 9 and y = 6.