Math 9 Surface Area Part 1 PDF
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Uploaded by SolicitousJadeite1757
Dr. Emily Stowe Public School
2024
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Summary
This document includes a collection of questions and solutions related to surface area calculations suitable for math students in high school. The questions cover various shapes like squares, rectangles, triangles, circles, cubes, and rectangular prisms. This document also includes examples of calculating surface area.
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Math 9 – September 19, 2024 Quiz Review – September 13 – Answers 1. Real Number System a) 0,6 b) 6 c) -3, 0, 6 d) 6, -3, 0, 1/8, 1.6 or 16/10 e) 4.61593…, √7 f) All 2. Square Roots a) √625 = √252 = 25 b) √144 = √122 = 12 c) √2.5 = 25/10 = 0 N...
Math 9 – September 19, 2024 Quiz Review – September 13 – Answers 1. Real Number System a) 0,6 b) 6 c) -3, 0, 6 d) 6, -3, 0, 1/8, 1.6 or 16/10 e) 4.61593…, √7 f) All 2. Square Roots a) √625 = √252 = 25 b) √144 = √122 = 12 c) √2.5 = 25/10 = 0 Not a perfect square d) √64/100 = √82/102 = 8/10 or 4/5 or 0.8 e) √0.0121 = √121/1000 = √112/1002 = 11/100 or 0.11 f) √400/196 = √202/142 = 20/14 = 10/7 g) √16/10 = √42/102 = 0 Not a perfect square h) √25/1 = √52/12 = 5/1 = 5 i) √0.009 = √92/10002 = √32/10002 = 0 Not a perfect square Surface Area In measurement: Perimeter → 1-Dimeninsional, units – cm/m Area → 2-Dimensional, units- cm x cm = cm2 Volume → 3- Dimensional, units- cm x cm x cm = cm3 Area Examples Square: Area = s x s = s2 s s Rectangle: Area = length x width w l Triangle: Area = length x width w 2 l height → by definition: Area = base x height = ½bxh 2 base → If not a right triangle, you will have to find the height. Perpendicular (meets @ 90 degrees) 6cm Bisector (cut in half) 4 cm 2 cm 6cm height Use Pythagoras to find height. 2 cm Circle: Notes: Use 3.14 for 𝜋 r d = Diameter r = Radius d 𝑺𝑨 = 𝝅𝒓𝟐 Surface Area of Regular Prisms Cube: S2 s S 2 SA = (6 sides)(s x s) S2 S 2 =6s2 s Rectangular Prism: 3 pairs of matching areas h (h x w), (l x w), (h x l) SA = 2(h x w) + 2 (l x w) + 2 (h x l) l w Triangular Prism: w 2 equal triangular ends 3 sides (rectangle) SA= 2(½ bh) + (l x w) + (l x w) + (l x w) l b Isosceles an equilateral triangle. Cylinder: r r Circumference = 2 𝜋𝑟 2 h C = 𝜋𝑑 SA= 2 𝝅𝒓𝟐 + 𝟐𝝅𝒓𝒉 r circumference sdfasdf asf Examples: Find the SA Ex. 1 SA= 2(l x w) + 2(w x h) + 2(h x l) = 2(6 x 4) + 2(4 x 3) + 2(3 x 6) 3cm 6cm =2(24) + 2(12) + 2(18) = 48 + 24 + 36 SA = 108 cm2 Ex. 2 SA= 2(½bh) + 3(l x w) 4cm = 2(4x4) + 3(8 x 4) 2 4cm = 2(8) + 3(32) 8cm = 16 + 96 SA = 112cm2 4cm Ex. 3 Step 1 find height using Pythagoras. 6cm Step 2 find surface area. 5cm h 4cm 3cm 5cm h 3cm
