Algebra 22.3
Pinkston
SAT Question
If x + 3 = 13, what does x – 5 equal?A. 5B. 8C. 10D. 11E. 15
10
5 5
x
So x
Literal Equation: An equation that contains more
than one variable.
Formula: A literal equation that is a rule for giving specific
calculations.
Example 1: Solve W = EI for I
W EI
E E
WI
E
Example 2: Solve for b.
5( 20)
2A b
550
2A b
(2) (2)5
502
(2)A b
2 5 100A b
2 5 100A b 100 100
2 100 5A b 5 5
2 100
5
Ab
Example 3: Solve for b.
1(2) 2
2A bh
1
2A bh
2A bhh h
2Ab
h
3 5Q r p
Example 4: Solve for p.
3 5Q r p 3 3r r
5 53
5
Q rp
Example 5: Solve A = P + Prt for P.
A = P + Prt
A = P(1 + rt)1+ rt1+ rt
1
AP
rt
Example 6: Solve T = Q + Qiy for Q.
T = Q + Qiy
T = Q(1 + iy)1+ iy1+ iy
1
TQ
iy
Classwork:
2-24 even/72
Get ready for a “Small Quiz” to be written
on your grade sheet.
Solve:A twenty foot cord is divided into two parts. One part is 2 less than twice the other. What is the measurement of each part?
Quiz. Copy the problem and write the answer.
Put your grade paper on the front of your row, quiz side down.