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Activity 1 of 2Mr. Hall needs lights installed in his house and is trying to decide between two electric companies. ABC Electric's charges can be represented by the equation y = 50x + 75 Two Electricians' charges can be represented by the following table: X: 0 1 2 4Y: 70 130 190 250Complete each of the 2 activities for this Task.Which company charges more per hour?Activity 2 of 2Mr. Hall is estimating he needs about 5 hours of work done. Which company should he choose if he is trying to save money? Show your work or explain your reasoning.

1 Answer

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1) Two Electricians' charges more per hour

2) Mr Hall should choose ABC electric to save money

Step-by-step explanation:

ABC Electric's charges :

y = 50x + 75

Two Electricians' charges is shown in the table

To determine which company charges more per hour, let's compare their charages

1) y = 50x + 75

when x = 1 hour

y = 50(1) + 75 = 50 + 75

y = $125

From the table, when x = 1

y = $130

$130 > $125

The charge of Two Electricians' for 1 hour is more than that of ABC Electric's charges

Hence, Two Electricians charges more per hour

2) For 5hours, x = 5

inserting the value for x in ABC electric charges:

y = 50(5) + 75

y = 250 + 75

y = $325

There is no value for x = 5 on the table given

we need to find an equation for it

Equation of line: y = mx + c

Rate of change = slope = change in y/change in x

Using points: (0, 70) and (1, 130)

Rate of change = (130-70)/(1-0) = 60/1

Rate of change = slope = 60

The y-intecept is when x = 0

y-intercept = c = 70

equation for Two Electricians' charges :

y = 60x + 70

when x = 5

y = 60(5) + 70

y = 300 70

y = $370

$370 > $325

ABC electric cost less for 5hrs

Mr Hall should choose ABC electric to save money

User Stephen M
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