Respuesta :

Answer:

Step-by-step explanation:

First one:

x² + 13x + 15 = 2x + 5

First, combine like terms and place all your results on the left side of this equation:  x² + 11x + 10 = 0.  Note that (1)(10) = 10 and that 1 + 10 = 11.  Thus, this last result factors easily into (x + 1)(x + 10) = 0, so that x + 1 = 1 and x = -1 and also x + 10 = 0 yields x = -10.  The solutions (roots, zeros) of the given equation are {-10, -1}.

Second one:

x² = 2x + 63

Again, consolidate all three terms on the left side with "=0" on the right side:

x² - 2x - 63 = 0.  Note that 7(-9) = -63 and that -9 + 7 = -2.  Thus, in factored form we have (x - 9)(x + 7) = 0, ans so the roots are {-7, 9}.