Question

The temperature decreased overnight by 15.2°C to a temperature of –12.8°C. Suppose t represents the temperature before it decreased.

Which equation can be used to represent this situation?



A.


t – 15.2 = –12.8


B.


t + 12.8 = –15.2


C.


t – 12.8 = 15.2


D.


t – (–15.2) = –12.8

Answer 1

Option a

Explanation:

Given that temperature originally was t.

It was decreasing continuously overnight.

finally the temperature reading was -12.8 degree C

Given that it decreased by 15.2 degree C

This means original temperature -15.2 = new temperature -12.8

i.e. t-15.2 = -12.8 is the correct equation.

Option a is right.

Verify:

Solve to get t = 15.2-12.8 = 2.4

Hence when 2.4 decreases by 15.2 we get new temperature

= 2.4-15.2 = -12.8