8TH GRADE MATH CHART

By Angelica Gonzalez

2nd Period

Volume

The amount of space, measured in cubic units, that an object takes up.

Prism: V=Bh Cylinder: V=Bh Pyramid: V=1/3Bh Cone: V=1/3Bh Sphere: V=4/3(3.14)r^3

Word Problem

A cylinder has a diameter of 14 inches and a height of 21 inches. What is its volume?

21 in.

14 in.

V=BhA=3.14(r^2)

A=3.14(7^2)A=3.14(49)A=153.86

V=153.86(21)

V = 3,231.06 in.

Pi The ratio of the circumference to the diameter of

a circle; equal to about 3.141592+.

Word Problem

Area The area of a figure is the number of squares

required to cover it completely.

Square: A=s^2 Rectangle: A=lw or A=bh Triangle: A=1/2bh or A=bh/2 Circle: A=(3.14)r^2

Word Problem

A circle has a radius of 5 cm. Find the area.

5 cm.

A=3.14(5)^2A=3.14(25)

A = 78.5 cm.

A = 3.14 (r^2)

Perimeter A path that surrounds an area.

Square: P=4s Rectangle: P=2l+2w or P=2(l+w)

Word Problem

What is the perimeter of this figure?

9 in.

4 in.

P = 2(l + w)

P = 2 (9 +4)P = 2 (13)

P = 26 in.

Circumference The size of something as given by the distance

around it.

Circle: C=2(3.14)r

Word Problem

If a circle has a diameter of 8 inches, what is the circumference?

3.14 * 8 = 25.12 in.

8 in.

Surface Area A measure of the number of square units needed to cover the

faces or surfaces of a figure.

Cube(total): S=6s^2 Prism(lateral): S=Ph Prism(total): S=Ph+2B Pyramid(lateral): S=1/2Pl Pyramid(total): S=1/2Pl+B Cylinder(lateral): S=2(3.14)rh Cylinder(total): S=2(3.14)rh+2(3.14)r^2 or S=2(3.14)r(h+r)

Word Problem

Find the lateral surface area a cylinder with a height of 12 cm. and a diameter of 8 cm.

12 cm.

8 cm.

S = 2(3.14)rh

S = 6.28 (4) hS = 25.12 (12)

S = 301.44 cm.

Pythagorean Theorem

a^2+b^2=c^2

Word Problem

Simple Interest Formula

I = prt

Word Problem

P

P represents the perimeter of the base of a three-dimensional figure.

Word Problem

B

B represents the area f the base of a three-dimensional figure.

Word Problem