# Parallelogram

See how to solve a parallelogram

(sides/angles/diagonals/area).

6 examples and their solutions.

## Parallelogram: Definition

### Definition

## Parallelogram: Sides

### Property

### Example

2x + 1 = 9

2x = 8

x = 4

y + 4 = 6

y = 6

x = 4, y = 6

Close

### Example

OPQR: Parallelogram.

Coordinates of point Q = ?

Solution Coordinates of point Q = ?

↓

Q(1 + 6, 4 + + 2)

= (7, 6)

[1]

PQ and OR are parallel and congruent.

→ (change of P → Q) = (change of O → R)

= (+6, +2)

→ (change of P → Q) = (change of O → R)

= (+6, +2)

Close

## Parallelogram: Angles

### Property

m∠1 = m∠1'

m∠2 = m∠2'

m∠[blue] + m∠[green] = 180

### Example

m∠A, m∠B, m∠C = ?

Solution m∠A + 70 = 180

m∠A = 110

↓

↓

↓

m∠A = 110

m∠B = 70

m∠C = 110

Close

## Parallelogram: Diagonals

### Property

### Example

3x - 2 = 7

3x = 9

x = 3

2y = 10

y = 5

x = 3, y = 5

Close

## Parallelogram: Area

### Formula

A = bh

### Example

Area?

Solution A = 9⋅5

= 45

Close

### Example

Area?

Solution A = 11⋅8

= 88

Close