Answer:
What Wally did wrong is that it is supposed to be (4a-5)(a-4)
In order to get -21 a. He was supposed to use negative 5 and 4 to get to negative 21
If he used (4a+5)(a+5)
The answer will be positive 21 and that's not what the problem is asking
Step-by-step explanation:
Answer:
x = 20
Step-by-step explanation:
Assuming you require the value of x
The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.
7x - 15 is an exterior angle of the triangle, thus
7x - 15 = x + 28 + 4x - 3 , that is
7x - 15 = 5x + 25 ( subtract 5x from both sides )
2x - 15 = 25 ( add 15 to both sides )
2x = 40 ( divide both sides by 2 )
x = 20
Answer:
-2(-3n - 12)
Step-by-step explanation:
2x -10 = 30
add ten to both sides
2x = 40
divide by two
x = 20
Answer:
Angle 1 = 22°
Angle 2 = 68°
Angle 3 = 68°
Angle 4 = 90°
Step-by-step explanation:
It is a rhombus by the definition:
A rhombus is a quadrilateral whose all four sides are equal in length and opposite sides are parallel to each other. However, the angles are not equal to 90°.
The properties of rhombus is:
(1) Opposite angles are equal
(2) All sides are equal and, opposite sides are parallel to each other
(3) Diagonals bisect each other perpendicularly
(4) Sum of any two adjacent angles is 180°
By property (3):
Angle 4 = 90°
By (1) and properties of isosceles triangle in the top right triangle:
Angle 2 = Angle 3 = 68°
In the top triangle:
Angle 1 + Angle 2 + 90° = 180° (Angle sum of triangle)
Angle 1 = 22°
