It's a maths question worth 4 marks

a = 3, b= - 4 and c = - 4

expand the left side using FOIL

(2x + 1)(ax + b) = 2ax² + 2bx + ax + b = 2ax² + x(2b + a) + b

compare the coefficients of expressions on left and right sides.

compare 2ax² + x(2b +a) + b with 6x² - 5x + c

coefficients of x² terms → 2a = 6 ⇒ a = 3

coefficients of x terms → 2b + a = - 5 → 2b + 3 = - 5 → 2b = - 8 ⇒ b = - 4

constant terms c = b = - 4

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

answer: on graphs, the open and closed circles, or vertical asymptotes drawn as dashed lines us identify discontinuities.

as before, graphs and tables allow us to estimate at best.

when working with formulas, getting zero in the denominator indicates a point of discontinuity.

when working with piecewise-defined functions, check for discontinuities at the transition points where one piece ends and the next begins.

step-by-step explanation: