MatemáticasBásico1 respuestas

[tex](r + 2)(r - 5) + 7r ^ 2 = (2r - 3)(4r + 1)[ / tex]?

[tex](r + 2)(r - 5) + 7r ^ 2 = (2r - 3)(4r + 1)[ / tex].

En resumen

R² - 3r - 10 + 7r² = 8r² - 10r - 3 8r² - 8r² - 3r + 10r - 10 + 3 = 0 7r - 7 = 0 r = 7 / 7 r = 1 comprobacion (1 + 2)(1 - 5) + 7(1²) = (2(1) - 3)(4(1) + 1) (3)( - 4) + 7 = ( - 1)(5) - 12 + 7 = - 5 - 5 = - 5.

Mejor respuesta

Ximenamera29
3

R² - 3r - 10 + 7r² = 8r² - 10r - 3

8r² - 8r² - 3r + 10r - 10 + 3 = 0

7r - 7 = 0

r = 7 / 7

r = 1

comprobacion

(1 + 2)(1 - 5) + 7(1²) = (2(1) - 3)(4(1) + 1)

(3)( - 4) + 7 = ( - 1)(5) - 12 + 7 = - 5 - 5 = - 5.