Question

Solve these 3 questions

1: 19−4c=17

2: 1.1x+1.2x−5.4=−10

3:The cost C (in dollars) of making n watches is represented by C=15n+85. How many watches are made when the cost is $385?

Answer 1

1.

`19 - 4c = 17 \\ 4c = 19 - 17 \\ 4c = 2 \\ \\ { \underline{c = (1)/(2) }}`

2.

`1.1x + 1.2x - 5.4 = - 10 \\ \\ 2.3x = - 4.6 \\ { \underline{ \: \: x = - 2 \: \: }}`

3.

`c = 15n + 85 \\ 385 = 15n + 85 \\ 15n = 300 \\ { \underline{ \: \: n = 20 \: \: }}`