M1A Warm Up: Just try this and see if you can remember… The distance from Raleigh to Wilmington is...
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Transcript of M1A Warm Up: Just try this and see if you can remember… The distance from Raleigh to Wilmington is...
M1A Warm Up:Just try this and see if you can remember…
The distance from Raleigh to Wilmington is 120 miles, the distance from Wilmington to Charlotte is 200 miles, and the distance from Raleigh to Charlotte is 160 miles. Do the three towns form a right triangle? Explain.
Yes; The Pythagorean Theorem is true for these three values. 1602 + 1202 = 2002
Objective:Students will be able to:
•Use formulas for rectangles, triangles, circles, cylinders, cones.•To solve literal equations
TriangleSo then what happens if we
cut a rectangle in half? What shape is made?
2 Triangles
So then what happens to the formula?
TriangleSo then what happens if we
cut a rectangle in half? What shape is made?
2 Triangles
So then what happens to the formula?
TriangleSo then what happens if we
cut a rectangle in half? What shape is made?
2 Triangles
So then what happens to the formula?
bh
TriangleSo then what happens if we
cut a rectangle in half? What shape is made?
2 Triangles
So then what happens to the formula?
bh2
A prism is a three-dimensional figure named for the shape of its bases. The two bases are congruent polygons. All of the other faces are parallelograms. A cylinder has two circular bases.
7 cm
Find the area of the circle.
A = π r
2
1. Substitute the radius into formula.
A = π (7)2
2. Use 3.14 as an approximation for π.A = 3.14(49)
A = 153.86 cm2
3. Don't forget to label the units as square units.
VOLUME OF PRISMS AND CYLINDERSWords Numbers Formula
Prism: The volume V of a prism is the area of the base B times the height h.
Cylinder: The volume of a cylinder is the area of the base B times the height h.
B = 2(5)= 10 units2
V = 10(3)
= 30 units3
B = p(22)= 4p units2
V = (4p)(6) = 24p 75.4 units3
V = Bh
V = Bh
= (pr2)h
Show Brainpop video on Cylinders.
Ex 1: Find the volume of each figure to the nearest tenth.
A rectangular prism with base 2 cm by 5 cm and height 3 cm.
= 30 cm3
B = 2 • 5 = 10 cm2
V = Bh
= 10 • 3
Area of base
Volume of a prism
Ex 2: Find the volume of the figure to the nearest tenth.
4 in.
12 in.
= 192 p 602.88 in3
B = p(42) = 16p in2
V = Bh
= 16p • 12
Area of base
Volume of a cylinder
A pyramid is named for the shape of its base. The base is a polygon, and all of the other faces are triangles. A cone has a circular base. The height of a pyramid or cone is measured from the highest point to the base along a perpendicular line.
13V = • 9 • 10
V = 30 94.2 in3
V = Bh13
B = (32) = 9 in2
Use 3.14 for .
Ex 7: Find the volume of the figure.
1) Solve 2x - 4y = 7 for xTo get x by itself, what is the first step?
1. Add 2x2. Subtract 2x3. Add 4y4. Subtract 4y
Answer Now
L1) Solve 2x - 4y = 7 for x1. Draw “the river”2. Add 4y to both
sides3. Simplify4. Divide both sides
by 25. Does it simplify?
+ 4y + 4y
2x = 7 + 4y
2 27 4
2
yx
x = 2y + 3.5
L2) Solve 2x - 4y = 7 for yTo get y by itself, what is the first step?
1. Add 2x2. Subtract 2x3. Add 4y4. Subtract 4y
Answer Now
L2) Solve 2x - 4y = 7 for y1. Draw “the river”
2. Subtract 2x from both sides
3. Simplify
4. Divide both sides by -4
5. Does it simplify?
- 2x - 2x
-4y = 7 - 2x
-4 -47 2
4
xy
y = 0.5x - 1.75
L3) Solve for y.
What is the first step?
y a3
c
1. Multiply by 32. Divide by 33. Add a4. Subtract a
Answer Now
L3) Solve for y:y a
3c
1. Draw “the river”
2. Clear the fraction – multiply both sides by 3
3. Simplify
4. Subtract a from both sides
5. Simplify
y + a = 3c
-a -a
y = 3c - a
3 33
y ac
L4) Solve for y: 4x – 2y = 12
1. Draw “the river”
2. Subtract 4x from both sides
3. Simplify
4. Divide both sides by -2
5. Does it simplify?
- 4x - 4x
-2y = 12 – 4x
-2 -2
y = -6 + 2x
or y = 2x - 6Yes!
1. L = V - WH
2.
3.
4.
L5) The formula for the volume of a rectangular prism is V = LWH. Which equation solves the formula for L?
LV H
W
LVW
H
LV
HW Answer Now
1. h = 3Vb
2.
3.
4.
L6) The formula for the volume of a pyramid is V = . Which equation solves the formula for h?
Answer Now
1
3bh
h 3b
V
h 3V
b
h V
3b