agentkronus agentkronus

02-03-2015
Mathematics

contestada

Find x when P = 21.

P = x(x - 1) / 2

Respuesta :

konrad509 konrad509

02-03-2015

[tex]21=\dfrac{x(x-1)}{2}\\ 42=x^2-x\\ x^2-x-42=0\\ x^2+6x-7x-42=0\\ x(x+6)-7(x+6)=0\\ (x-7)(x+6)=0\\ x=7 \vee x=-6[/tex]

Answer Link

Otras preguntas

The patient ledger is also referred to as

Choose the graph which matches the function f(x) 2^x+2

What is the volume of this right rectangular prism. 7 feet length 2 feet width and 3.5 feet Height

The________ immune system consists of cellular immunity and humoral immunity.Choices:Adaptive Innate

Please help! On part B!

Which sentence contains an error in pronoun-antecedent agreement?

snakes cannot close their eyes true or false

What is the approximate area of the figure

Factor. 8x5+4x2−12 Question 1 options: 4(2x5+x2−3) 4(2x5+4x2−12) 4x2(2x3+x−3)

Help with Spanish homework