algebra help

Question

estimate 42 squared to the nearest 10th 

 

what 2 integers is 42 squared between 

 

one cell phone company charges 20 dollars plus 15 cents per min used write and solve an equasion to find the number of mins you must talk to have the same cost for both calling plans 

 

 

is the following a function 

(2,3)

(3,5)

(4,1)

(5,2)

Answer 1

Maleeha, are you asking for the square root of 42? If so, it falls between 6 and 7, since 6² = 36 and 7² = 49. 

 

42 is about half way between 36 and 49, so let's start with 6.5.

 

6.5(6.5) = 42.25

 

Since it's slightly closer to 36, let's try 6.4.

 

6.4(6.4) = 40.96

 

42.25 is way closer to 42 than 40.96, so we're gonna go with 6.5.

 

You only list one calling plan, but it's .15m + 20. Do the same with the other plan, set them equal to each other, and solve for m.

 

A function has only one output for each input, or one y for each x. Since you have four different inputs, you have a function, no matter the outputs.

 

For example, (2,2),(3,2),(4,2),(5,2) is a function, but (2,2),(2,3),(2,4),(2,5) is not.