Answer to Student Resources Crane Strain: Math Focus

The Pythagorean is used to find the missing truss members:

a2 + b2 = c2

****Please Note: This formula is for right triangles only!****

b

a

c

Answer to Student Resources Crane Strain: Math Focus

Problem 1:

Given: c = 19; b = 17

Find: aEquation: a2 + b2 = c2

Solve: a2 + 172 = 192

a2 + 289 = 361 a2 = 361 – 289 a2 = 72 a = √72 = 8.5

19

17

Answer to Student Resources Crane Strain: Math Focus

Problem 2:

Given: a = 5; b = 13

Find: cEquation: a2 + b2 = c2

Solve: 52 + 132 = c2

25 + 169 = c2

c2 = 194 c = √194 = 13.9

5

13

Answer to Student Resources Crane Strain: Math Focus

Problem 3:

Given: c = 20; a = 10

Find: bEquation: a2 + b2 = c2

Solve: 102 + b2 = 202

100 + b2 = 400 b2 = 400 – 100 b2 = 300 b = √300 = 17.3

2010

Answer to Student Resources Crane Strain: Math Focus

Problem 4:

Given: a = 5; b = 14

Find: cEquation: a2 + b2 = c2

Solve: 52 + 142 = c2

25 + 196 = c2

c2 = 221 c = √221 = 14.9

5

14

Answer to Student Resources Crane Strain: Math Focus

Problem 5:

Given: a = 13; b = 6

Find: cEquation: a2 + b2 = c2

Solve: 132 + 62 = c2

169+ 36 = c2

c2 = 205 c = √205 = 14.3

13

6

Answer to Student Resources Crane Strain: Math Focus

Problem 6:

Given: c = 23; b = 8

Find: aEquation: a2 + b2 = c2

Solve: a2 + 82 = 232

a2 + 64 = 529 a2 = 529 – 64 a2 = 465 a = √465 = 21.6

238