6-1 First Day Interior Exterior Angle Sum

quadrilateral has 4 sides. So plugging into the formula.

(4-2) • 180

Find the value of x.

This is a quadrilateral. 4 sides.

So first

(4-2)•180

equals 360°.

So the 4 angles add up to 360.

x+(2x+5)+x+(2x+7) = 360

Then solve for x.

This is a quadrilateral. The 4 angles add up to 360.

Solve for x.

From the value of x that you had from the previous problem now find the measurement of angle K.

This is a pentagon.

(5-2)•180

540°

So in a pentagon the 5 angles add up to 540°

90°+(2x+10)°+x°+(2x-20)°+90°=540°

Solve for x.

This is a pentagon. The 5 angles add up to 540°

Find the value of x.

From the value of x that you had from the previous problem now find the measurement of angle Z.

These are exterior angles. Remember that the exterior angles always add up to 360°.

So

2x+88+x+10+x+2+52=360

Solve for x.

Solve for x.

Find the sum of the measures of the angles of a nonagon. (9 sides)

(n-2) • 180

(9-2) • 180

Find the sum of the measures of the angles of a heptagon. (7 sides)

(n-2) • 180

Find the measure of each interior angle of a regular quadrilateral.

n = 4

Here is the formula for this

So plugging in 4 for n.

Find the measure of each interior angle of a regular pentagon.

n = 5

Here is the formula for this

Find the measure of each angle of a regular octagon.

n = 8

So plugging in 8 for n

Find the measure of each angle of a regular nonagon.

n = 9