Answer:
It makes the calculation easy and quick.
Step-by-step explanation:
- <em>Commutative Property of multiplication</em>
- <em>The product of two or more real numbers is not affected by the order in which they are being multiplied. In other words, real numbers can be multiplied in any order because the product remains the same. </em>
<u>When you multiply as it is given:</u>
- 5×87×2=870
- Step 1) 5×87 = 435
- Step 2) 435×2 = 870
<u>Using the commutative property makes it much easier:</u>
- 5×2×87 = 870
- Step 1) 5×2 = 10
- Step 2) 10* 87 = 870
2{(cos^210+isin^210)}^2
2(cos^210-sin^10+2i*cos10*sin10)
2(cos20+i*sin20)
cos^2Ф-sin^2Ф=cos2Ф and 2sinФcosФ=sin2Ф here Ф=10°
First add the whole numbers;
5 + 3 = 8
then add the numerators( you could add them cause they have like denominators);
8/12 + 5/12 = (8+5) = 13/12
13/12 = 1 1/2
so your final answer would be: 9 1/2 (I added the whole numbers)
<span>numerical expression</span>
Let’s say we have x gallons of brand 1 antifreeze and y gallons of brand 2 antifreeze. We know we need a total of 140 gallons, so one equation to relate the variables would be x+y=140. We also know that our final mixture should have 60% antifreeze, so another equation would be the weighted average of the two brands: .55x+.80y140=.60. (The weighted average is basically multiplying each % (55 and 80) by the number of gallons you have (x and y
) and adding those together, and dividing that by the total number of gallons (140). This equals the % of the final mixture (60).)
Now we have a system of two equations that we can solve.
x+y=140
.55x+.80y140=.60
*rearrange first equation to solve for y
:
y=140−x
*substitute this value in for y
in the second equation:
.55x+.80(140−x)140=.60
*use algebra and solve for x
:
The algebra shouldn’t be too complex, and I’m hoping you’re asking this about the setup rather than the actual algebra, and I’m lazy, and I used a calculator to solve this, and this is probably a long run-on sentence, and I got x=112
.
*plug this in to first equation and solve for y
:
y=140−112=28
x=112,y=28
112 gallons of brand 1 antifreeze, 28 gallons of brand 2 antifreeze. That’s a whole lot of antifreeze.
thanx heyaaaaaa
