Question #1: t = unknown number
15 + 6t = 81
[The sum(addition) of 15 and 6 times(multiplication) a number t is(=) 81.
So 15 plus 6t(6 times t) equals 81.]
To find t, isolate/get the variable "t" by itself in the equation:
15 + 6t = 81 Subtract 15 on both sides
15 - 15 + 6t = 81 - 15
6t = 66 Divide 6 on both sides to get "t" by itself
t = 11 The number(t) is 11
Question #2: h = the number of hours
55h + 40 = 190
[The electrician charges $40 plus $55 per hour(h) that she works, and the total charge is(=) $190]
To find h, isolate/get the variable "h" by itself in the equation:
55h + 40 = 190 Subtract 40 on both sides
55h = 150 Divide 55 on both sides to get "h" by itself
h = [tex]\frac{150}{55}[/tex] Simplify the fraction
[tex]h=\frac{30}{11}[/tex] The electrician works 30/11 hours (or 2.7272727272....repeating forever)
Question #3: m = the number of miles traveled
0.75m + 1.75 = 4.75
[The taxi charges $40 plus $0.75 per mile(m), and the total charge is(=) $4.75]
To find m, isolate the variable:
0.75m + 1.75 = 4.75 Subtract 1.75 on both sides
0.75m = 3 Divide 0.75 on both sides to get "m" by itself
m = 4 The trip is 4 miles.
