Download Section 3.7.notebook

Section 3.7.notebook
November 09, 2012
Section 3.7 ­ Formulas and Functions
formula
an algebraic equation that relates two or more variables
Examples:
1. Solve A = lw for w.
2. Solve I = prt for t.
3. Solve 2x ­ y = 9 for y.
4. Solve 2x ­ y = 9 for x.
5. a. Solve 5x + y = ­8 for y.
b. Use the result to find y when x = ­2, ­1, 0, and 1.
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Section 3.7.notebook
November 09, 2012
6. Solve V = 1s2h for h.
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(Volume of a square pyramid)
7. Solve 5(1 + y) = ­12(x ­ y) for y.
8. ­3x + 4y ­ 5 = ­14
9. 4x ­ 3(y ­ 2) = 15 + y
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Section 3.7.notebook
November 09, 2012
10. y ­ 7 = ­2x
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11. Use the formula d = rt, where d is the distance traveled at a rate of r for time t.
a. Solve the equation for t.
b. Determine how long it will take an airplane to travel 2000 miles if it flies 200 miles per hour, 400 miles per hour, and 600 miles per hour.
12. Use the formula I = Prt, where I is the simple interest on an investment of P dollars at an interest rate r for t years. a. Solve the equation for r.
b. Find the interest rate r for an investment of $1200 that earned $66 in interest for one year.
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Section 3.7.notebook
November 09, 2012
Homework
p. 177­178
#12­30 Evens
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