hitanpat hitanpat

15-09-2019
Mathematics

contestada

If a+b+c=7 and ab+bc+ca=20 find the value of a^2+b^2+c^2

Respuesta :

jimrgrant1 jimrgrant1

15-09-2019

Answer:

9

Step-by-step explanation:

Using the identity

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

Subtract 2(ab + bc + ca) from both sides, then

a² + b² + c² = (a + b + c)² - 2(ab + bc + ca) = 7² - 2(20) = 49 - 40 = 9

Answer Link

Otras preguntas

At the book store, Dan bought 14 books about the Civil War, and 8 magazines about Abraham Licoln. if each book cost $13 dollars and magazines cost $6 dollars, h

Which value represents the slope of the line that has an x-intercept at (-4,0) and a y-intercept at (0,-12) in the coordination plane?

How many solutions does the system of equations below have? 2x + y = 3 8x + 4y = –11

The C/Kg or R is usually the unit measured in? a) C/Kg b) R c) Cannot be determined

can someone please help me really

Some historians have claimed that by allowing Anglo immigration into Texas, the Mexican government ultimately lost the territory. Support or refute this claim w

which food is the temperature danger zone tdz

How do you write 90% as a decimal??

from the kindness of your heart, pls help me :D

A unit that has been reinforced with elements of another unit has a _____ symbol at its upper right corner. A unit that has elements detached has a _____ symbol