How many of these equations have the solution x
=
12
x
=
12
?

x
−
2
=
10
x
−
2
=
10
x
2
=
24
x
2
=
24
10
−
x
=
2
10
−
x
=
2
2x1=25
2x−1=25

a)x−2=10

b) 2x=24

Two equations have have the solution

x = 12

Question:

How many of these equations have the solution x=12 ?

x−2=10

2x=24

10−x=2

2x−1=25

Step-by-step explanation:

To determine which of the above equations have x= 12, we would solve for x in each of the equations.

a) x−2=10

Collecting like terms

x = 10+2

x = 12

This equation has x= 12 as a solution

b) 2x =24

Divide through by coefficient of x which is 2

2x/2 = 24/2

x = 12

This equation has x= 12 as a solution

c) 10−x=2

Collecting like terms

10-2 - x = 0

8 - x = 0

x = 8

d) 2x−1=25

Collecting like terms

2x = 25+1

2x = 26

Divide through by coefficient of x which is 2

2x/2 = 26/2

x = 13

Note: that (b) x2 = 24 from the question isn't clear enough. I used 2x = 24.

If x2 = 24 means x² = 24

Then x = √24 = √(4×6)

x = 2√6

Then the number of equations that have the solution x = 12 would be 1. That is (a) x−2=10 only

answer: 0.1,0.85

step-by-step explanation: