mutshinkx mutshinkx
  • 26-02-2021
  • Mathematics
contestada

If (a+b)(a-b)=21,a+b=7 and a-b=3 what Is the value of a

Respuesta :

sqdancefan
sqdancefan sqdancefan
  • 27-02-2021

9514 1404 393

Answer:

  5

Step-by-step explanation:

Add the latter two equations and you get ...

  (a +b) +(a -b) = (7) +(3)

  2a = 10 . . . . . . . . . . . . . . . simplify

  a = 5 . . . . . . . divide by 2

Answer Link

Otras preguntas

About how much alcohol can the average person metabolize, or break down, in an hour? 6 beers 2 beers 1 beer 4 beers
Which gas is the reactant in the chemical reactions of photosynthesis? nitrogen air oxygen carbon dioxide
What is the setting in The Giver?
which of the following statements best describes the work of Issac newton
Alen everage score after sixth test is 83 if Alen earns a score of 97 on the seventh test what is her new average
Help help help I’m Dumbbb
A rectangular picture frame is 5 inches wide and 10 inches tall. You want to make the area 6 times as large by increasing the length and width by the same amoun
On a quiz there are four multiple-choice questions worth 3 points each and two true/false questions worth 1 point each. Each multiple-choice question has five p
Main difference bwteen fats and oils
What is the difference between the greatest and least amounts rainfall??