(x−a)(x−b)
=(x+−a)(x+−b)
=(x)(x)+(x)(−b)+(−a)(x)+(−a)(−b)
=x2−bx−ax+ab
<h2><u><em>
=ab−ax−bx+x2</em></u></h2>
You want to compare the square root of 55 using "mental math". Start off by choosing two perfect squares that you can think of that are close to 55.
If you don't know perfect squares then start with the number 2 and multiply it by itself. 2 times 2 equals 4, so 4 is a perfect square.
Take the number 3, multiply it by itself, and so on. Do this for all the numbers until you find two perfect squares that are close to 55.
The two perfect squares closest to 55 are the square roots of 49 and 64. Find the square root of these numbers.
√49 = 7
√64 = 8
Calculate how far 55 is from 49 and 64. 55 is 6 digits away from 49 and 9 digits away from 64.
This means the square root of 55 will be closer to the square root of 49; 7. Since we know that it will be closer to 7, you can put the less than sign for your answer.
√55 < 7.7
(The actual square root of 55 is ~7.4, so we were correct in determining the answer without using a calculator!)
Making 10 chairs would take Marjorie and Blaine<u> </u><u>21 hours and 40 minutes</u>.
<h3>How long does it take to make 10 chairs?</h3>
The total time it takes Marjorie and Blaine to perform their respective tasks in building a chair is multiplied by 10 chairs, respectively. This time is known as their speed.
The resulting figures are summed to get the total time.
<h3>Data and Calculations:</h3>
The total time it takes Marjorie to build a chair is 15 hours (1.5 hours x 10)
The total time it takes Baline to sew cushions per chair is 400 minutes (40 x 10) or 6 hours and 40 minutes.
Therefore, the total time to build 10 chairs is 21 hours, 40 minutes (15 hours + 6 hours and 40 minutes).
Thus, making 10 chairs would take Marjorie and Blaine <u>21 hours and 40 minutes</u>.
Learn more about the time consumed at brainly.com/question/17146782
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-3x-12> 8x + 21
+12 +12
-3x > 8x + 33
-8x -8x
-11x > 33
————-
-11
x < -3
I moved the real numbers to one side and and the variable to the other side to solve for the inequality
I also remembered somewhere that if you divide by a negative number the inequality sign switches.
Answer:yes 2.324324 is a rational number
Step-by-step explanation:
