Kate decides to replace all the lights in her college apartment with energy saving light bulbs beginning this month. The packaging says the new bulbs will use 25% less electricity. If Kate's electric bill last month was $12.00 from bulb use alone, project how much Kate's electric bill will be this month for bulb use.

Kate's electric bill will be $9 for this month for bulb use only.

Step-by-step explanation:

Given:

Electricity bill lass month from bulb use = $12

Using new bulbs percent decrease in electricity = 25%

We need to find this month electric bill for bulb use.

Solution:

First we will find the reduction in bill after using new bulbs.

reduction in bill after using new bulbs can be calculated by percent decrease in electricity using new bulb multiplied by last month Electricity bill from bulb use only.

framing in equation form we get;

reduction in bill after using new bulbs =

Now we will find this month electric bill for bulb use only.

this month electric bill for bulb use only can be calculated by subtracting reduction in bill after using new bulbs from last month electric bill for bulb use only.

framing in equation form we get;

this month electric bill for bulb use only =

Hence Kate's electric bill will be $9 for this month for bulb use only.

13

step-by-step explanation:

169-1=168

168-3=165

165-5=160

160-7=153

153-9=144

144-11=133

133-13=120

120-15=105

105-17=88

88-19=69

69-21=48

48-23=25

25-25=0

since it took 13times to completely subtract it hence its square root is 13

d, x=8

step-by-step explanation:

simplifying

4x + -5 = 2x + 11

reorder the terms:

-5 + 4x = 2x + 11

reorder the terms:

-5 + 4x = 11 + 2x

solving

-5 + 4x = 11 + 2x

solving for variable 'x'.

move all terms containing x to the left, all other terms to the right.

add '-2x' to each side of the equation.

-5 + 4x + -2x = 11 + 2x + -2x

combine like terms: 4x + -2x = 2x

-5 + 2x = 11 + 2x + -2x

combine like terms: 2x + -2x = 0

-5 + 2x = 11 + 0

-5 + 2x = 11

add '5' to each side of the equation.

-5 + 5 + 2x = 11 + 5

combine like terms: -5 + 5 = 0

0 + 2x = 11 + 5

2x = 11 + 5

combine like terms: 11 + 5 = 16

2x = 16

divide each side by '2'.