3 years ago

If a +b+c=9 and a square +b square +square =1 then ab+bc+ca

Mathematics

1 answer:

MatroZZZ [7]3 years ago

4 0

Answer:

ab + bc + ca = 40

Step-by-step explanation:

Using the expansion identity

(a + b + c)² = a² + b² + c² + 2(ab + bc + ca) , that is

9² = 1 + 2(ab + bc + ca)

81 = 1 + 2(ab + bc + ca) ← subtract 1 from both sides

80 = 2(ab + bc + ca) ← divide both sides by 2

40 = ab + bc + ca

You might be interested in

7. Jackie wants to buy a new CD player It costs She has saved and has a coupon for off the Does Jackie have enough money to buy

Tomtit [17]

Ok, take 32.95 times 30% which is 32.95 times .30 which gives you 9.885. TAke 32.95 - 9.885 and gives u 23.065. So yes she has enough

8 0

4 years ago

Jenna bought books for $3 each and a game for $5. She spent a total of $26. How many books did she buy?

OleMash [197]

Answer:

she bought 7 books and 1 game. 1.)each=multiplication. 2.)and= addition.

Step-by-step explanation:

3.)26-5(the game)=21 divide by 3=7 books

4.)p-5=x divided by 3

3 0

3 years ago

Remember I’ll give brainliest This is the reposted question, I need help with number three

AURORKA [14]

Answer:

x is three the ratio show you what you need to divide by so triangle a is 3 and triangle b is 8 times larger than triangle a.

Step-by-step explanation:

7 0

4 years ago

(x - 3)2<br> k.<br> + 2x - 4 for x = 5

UNO [17]

Answer:

4k + 6

Step-by-step explanation:

3 0

4 years ago

Find the area of the circle when the circumference is 26 in

andrew11 [14]

Answer:

"None of the answers are correct."

Step-by-step explanation:

The formula for Area given the circumference is A = $\frac{C^{2} }{4\pi }$

$\frac{26^{2} }{4\pi } = 53.79437$

So none of the above are correct

3 0

3 years ago