Solving Equations by Addition,Subtraction, Multiplication, & Division
r-21= -37
-16
n - 2 = 4 - 2n
2
Expand & Simplify
3(a - 5) - 5a
-2a - 15
Twice a number is added to 4
2n + 4
A taxi driver uses this formula to work out the cost of a journey: C = 5 + 3m, where C is the cost of a journey in $ and m is the number of miles. A journey cost $29. Work out how many miles it is.
m = 8 miles
6x = -42
-7
3 - 4q = 10q +10
-0.5
Expand & Simplify
10a2 - 6a(2a - b)
-2a2 + 6ab
Three times a number is subtracted from 7.
7 - 3n
For a party, Fauzan allows 10 sweets per guest plus 15 spare sweets. Which formula should he use to work out the number of sweets (S) she should buy, for C guest?
S = 10C + 15
r + (-1/2) = -3/4
-1/4
5t - 9 = -3t +7
2
Expand & Simplify
5(x+3)-6(x-4)
-x + 39
Five times an unknown number is equal to 60. Find the number.
5n = 60
n = 12
Ikhwan is 25 older than his son. If the total age of them is 57, how old is his son?
Ikhwan's son = 16 y.o
(5/2)a = -25
-10
4(f -2) = -3(f +5)
f = -1
Expand and simplify
3a/2(4 - 2b) - 5ab
6a - 8ab
A number subtracted from 9 is equal to 2 times the number. Find the number.
9 - x = 2x
x = 3
Train ticket to Chicago for 3 adults and 1 child cost $95. An adult ticket cost $25 more than a child's ticket. Work out the cost of each ticket.
child's ticket = $5
adult's ticket = $30
5 = r/2
10
3(1 + d) - 5 = 2(d - 2)
d = -2
Expand & Simplify
2r(4 - r) - r(5 + 2r)
3r - 4r2
Adding nine to a number gives the same result as subtracting seven from three times the number. Find the number.
9 + x = 3x - 7
x = 8
Andrew is 5 years younger than Josephine. Four years later, Josephine will be twice as old as Andrew. Find their present ages.
a + 4 = 2(a - 5 + 4)
Josephine's present age is 6
Andrew's present age is 1