A = (1/2) b * h
h = b - 5
42 = (1/2) * b * (b - 5)
42 = (1/2) * b^2 - 5b
multiply both sides by 2 to clear the fraction (1/2)
2(42) = 2(1/2) *b^2 - 5b
84 = b^2 -5b
Since this is a quadratic equation, subtract 84 from both sides so that it is set = to zero.
b^2 - 5b - 84 = 0
Now factor.
(b - 12)(b + 5) = 0
b - 12 = 0; b = 12
b + 5 = 0; b = -5
You can't have a negative length so the answer is 12m
To check the answer:
A = (1/2) * 12* 7
A = 42 m^2
The percentage by which the cost is increasing will be 75%.
<h3>What is the percentage?</h3>
The quantity of anything is stated as though it were a fraction of a hundred. A fraction of 100 can be used to express the ratio.
The percentage of the 8th graders who want to go to the water slides is found from;
In the year 2000, a house was valued at $60 000.
In 2010, the same house was valued at $80 000.
The percentage value is found as;
Hence the percentage by which the cost is increasing will be 75%.
To learn more about percentages, refer to:
brainly.com/question/13450942
#SPJ1
Answer:
S = (1 times 5)times 6
Step-by-step explanation:
Question 5. Because there are 6 friends and each of them gets 5. one of them gets 5 But there are 6 friends so you multiply by 6. 6 times 5 is 30
Okay, so keeping mind that the equation for area is A = L x W, look at the measurements you already have. 5.5 x 10^5 is the length, and 4.2 x 10^4 is the width. Switch them into full form and use a calculator to multiply the two for the area in meters.
550000 x 42000 = 23100000000, which in scientific form is 2.31 × 10^10. So that's answer one.
For the second, in kilometers, just take the full measurement you already have, 23100000000 m, transfer it into kilometers, 23100000 km, and then find its scientific notation, 2.31 × 10^7. That's answer two.
To answer the last question for which is more suitable, just consider what number you'd prefer to look at: a bigger number or a smaller one. Since the kilometer measurement number is smaller, its correct.
Summarily, the answers are 2.31 × 10^10, 2.31 × 10^7, and square kilometers, in that order.
Answer:
<u><em>x=9</em></u>.
<em><u>perimeter=68</u></em>
<em><u>area=168</u></em>
Step-by-step explanation:
First find the side that has a exact number which would be the bottom 28cm then look at the opposite side (2x+10) in order to find x subtract 10 from 28 which gives you 18, now 2x means x multiplied by 2 so what multiplied by 2 = 18? 9 meaning <u><em>x=9</em></u>. Now you are going to want to plug 9 in to your short side (x-3) once you plug it in it should look like this 9-3 and 9-3=6 meaning the short side is 6cm. In order for you to find the perimeter you have to add the sides together so 28+28+6+6 wich <u><em>=68</em></u> and in order for you to find the area you have to multiply the length and the width so 28x6 which is <em><u>168</u></em>.
hope that helped :)