Let the cost of the hair dryer equal x.
The net cost plus a 40% markup equals 42, set up an equation and solve forex.
1.4x = 42
Divide both sides by 1.4
X = 42 / 1.4
X = 30
The net cost was £30
3x + 5 = 23
5 more than(addition) 3 times(multiplication) a variable(x) is(equals) 23
(you add 5 to 3x)
If you need to solve for "x", you need to isolate/get the variable "x" by itself in the equation:
3x + 5 = 23 Subtract 5 on both sides
3x + 5 - 5 = 23 - 5
3x = 18 Divide 3 on both sides to get "x" by itself

x = 6
Answer:

Step-by-step explanation:

(Multiplying each of the numbers also yields 240)
"The product" means you're multiplying the two numbers.
"a number" refers to a variable.
"increased" means you're adding.
2x + 7 = -36