Quadrilaterals

4.If in parallelogram ABCD, ∠A =(3x+3)° and ∠C=(4x-17)°, find the angles of ABCD.

5. In parallelogram ABCD, if ∠CAB = 35° and ∠BCA=65°, find the angles of ABCD.

1. Find the three other angles of parallelogram ABCD if ∠ A is equal to:
    a. 75 degrees   b. 62 degrees  c. 95 degrees  d. 82  1/2 degrees

6. In parallelogram ABCD, AC meets DB at O

    a. If DO=3x-1 and OB=2x+1 , find the length of DB.

    b. If AO=3x+1  and OC= 5x-3, find AC

7. In parallelogram ABCD, if ∠BAC= 42° and ∠BCA= 58°, find each angle of ABCD.

8. In parallelogram ABCD, if BC=3x+1 and AD=4x-2, find the lengths of BC and AD.

Since parallel sides are equal we have that  BC  = AD....so...

3x + 1 =  4x - 2      add 2 to both sides.......subtract  3x from both sides

3 = x

So......BC  = 3(3) + 1  = 10   =   AD

9. If AB=2x+1, DC=x+5 and BC=2x-1, find all the sides of parallelogram ABCD. Find its perimeter.

AB = CD  ...so

2x + 1  = x + 5     subtract x, 1 from both sides

x  = 4

And AD will = BC.......so the perimeter =

AB + BC + CD + DA  =

[2x + 1] + [2x - 1] + [  x + 5] + [ 2x -1] =

[ 2(4) + 1 ] + [ 2(4) - 1] + [ 4 + 5] + [ 2(4) - 1]  =

9 + 7 + 9 + 7    =   32