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3 years ago

Is it necessary to do all of the calculations to determine the sign of the product?

1 answer:

6 0

Depends on the formula, but with most cases yes, because you may have -3 as an answer, but adding only 4 makes it positive.

There are some cases where you could look at it and know the sign, like if I am adding -100 and -93, I know the answer will be negative

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3806 divided by 22=?

suter [353]

the answer to 3806 divided 22 is 173

8 0

4 years ago

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What is 1.5 as a ratio

Kitty [74]

Answer: 3/2

Step-by-step explanation:

3 0

3 years ago

In a right triangle ABC, CD is an altitude, such that AD=BC. Find AC, if AB=3 cm, and CD= 2 cm.

konstantin123 [22]

Consider right triangle ΔABC with legs AC and BC and hypotenuse AB. Draw the altitude CD.

1. Theorem: The length of each leg of a right triangle is the geometric mean of the length of the hypotenuse and the length of the segment of the hypotenuse adjacent to that leg.

According to this theorem,

$BC^2=BD\cdot AB.$

Let BC=x cm, then AD=BC=x cm and BD=AB-AD=3-x cm. Then

$x^2=(3-x)\cdot 3,\\ \\x^2=9-3x,\\ \\x^2+3x-9=0,\\ \\D=3^2-4\cdot (-9)=9+36=45,\\ \\\sqrt{D}=\sqrt{45}=3\sqrt{5},\\ \\x_1=\dfrac{-3-3\sqrt{5} }{2}0.$

Take positive value x. You get

$AD=BC=\dfrac{-3+3\sqrt{5} }{2}\ cm.$

2. According to the previous theorem,

$AC^2=AD\cdot AB.$

Then

$AC^2=\dfrac{-3+3\sqrt{5} }{2}\cdot 3=\dfrac{-9+9\sqrt{5} }{2},\\ \\AC=\sqrt{\dfrac{-9+9\sqrt{5} }{2}}\ cm.$

Answer: $AC=\sqrt{\dfrac{-9+9\sqrt{5} }{2}}\ cm.$

This solution doesn't need CD=2 cm. Note that if AB=3cm and CD=2cm, then

$CD^2=AD\cdot DB,\\ \\2^2=AD\cdot (3-AD),\\ \\AD^2-3AD+4=0,\\ \\D$

This means that you cannot find solutions of this equation. Then CD≠2 cm.

8 0

3 years ago

Read 2 more answers

12. Which two numbers whose ratio is 3 to 2 have a sum of 35? PLEASE HELP ASAP!!

Brut [27]

Answer:

14 and 21

Step-by-step explanation:

$You should solve the following linear equations : \\\frac{x}{y} = \frac{3}{2}\\ x+y=35$

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3 years ago

Find f(x) - g(x) *

Studentka2010 [4]

Answer:

3x^3+13x^2-3x+7

Step-by-step explanation:

I dont know if your question is complete.

f(x) - g(x)

$(4x^3+6x^2-3x+9)-(x^3-7x^2+2)\\4x^3+6x^2-3x+9-x^3+7x^2-2\\3x^3+13x^2-3x+7$

6 0

3 years ago