Extension Equations

Extension: Exercise 1 – Finding x.
What to do:
1) Rewrite the equation in a way that will help you find the x that makes the equation true.
2) Clearly explain the strategy you use to solve this equation.
3) Give the value of x that makes the equation true.
e.g. Equation: 19 = x + 47
Rewrite: x =19 - 47
Strategy: 47 – 19 = 28; 19 – 47 =-28
Solution: x = -28

(1) -45 + x = 76
x= -45-76
76- -45=121; -45-76=-121
x= -121

(2) x +17 = -15
x= -15 - 17
17- -15=32 ; -15 - 17=-32
x= -32

(3) 93 = x + 121
x=93-121
121-93=28; 93-121=-28
x=-28

(4) 72 + x = 199
x=72-199
199-72=127
x=127

(5) 63 = 46 - x
x=46-63
63-46=17 ; 46-63=-17
x=-17

(6) x - 29 = -51
x=-51-29
29- -51=80; -51-29=-80
x=-80

(7) 39 = 72 + x
x=72-39
39-72=-33; 72-39=33
x=-33

(8) x - 16 = -82
x= -82 - 16
16- -82=98; -82 - 16=-98
x=98

(9) 72 - x = -15
x=72- -15
-15-72=87; 72- -15=-87
x=87

(10) 22 = 44 + x
x=44-22
22-44=-22; 44-22=22
x=-22

Exercise 2 – Writing word problems Select 10 of these equations and write a word problem that the equation could be used to solve.

The temperature in the morning was -45o fahrenheit. In the afternoon the temperature rose to 76o celsius. What is the difference between the two temperatures?

It is 17o celsius in New Zealand. In Australia it is -15o fahrenheit. What is the difference between the two temperatures?

At 3:00p.m in the desert the temperature was 93o celsius. At 7:00p.m it rose to 121o celsius. What is the difference between the two temperatures?

At 11:30a.m it was 72o celsius in Africa. The temperature rose to 199o celsius at 6:00p.m. How much hotter was it at 6:00 then 11:30?

In the morning it was 46o celsius. In the afternoon the temperature rose to 63o celsius.

It was 29o celsius at 4p.m. At 1a.m it was -51o fahrenheit. How much colder is it now?

It was 72o celsius in the morning. In the evening it was 39o celsius. How much did the temperature drop in the evening?

In Fiji it is 16o celsius. In Antarctica it is -82o fahrenheit. How much colder is it in Antarctica than fiji?

In Australia the temperature is 72 degrees Celsius. in Poland the temperature is -15 degrees Celsius. What is the difference between the 2 temperatures?

In Africa the temperature is 45 degrees Celsius. In New Zealand it is 22 degrees Celsius. What is the difference between the two temperatures?