Question

Solve, by the method of completing the square :- -3x²+5x+12=0
please provide answers through a photo and don't give any unnecessary answer and give the correct answer answer (p please I request to all plz don't give)​

Answer 1

Step-by-step explanation:

Completing square method

-3x^2+5x+12 =0

x^2 -5/3x -4 =0.........Diving both side by -3

x^2 - 2*5/6x -4=0........ Multiply and divide by 2 to

middle term

x^2-2*5/6x = 4

x^2-2*5/6x +(5/6)^2 - (5/6)^2 = 4....... adding and

substracting by (5/6)^2

(x - 5/6)^2 - (5/6)^2 =4...... Using identity

(a - b) ^2 = a^2 -2ab+ b^2

(x - 5/6)^2 = 4 - 26/36

= 144 - 26 / 36

= 118/36

taking squre root on both side

x - 5/6 = (+-)√118/6

x = (+-)√118/6 + 5/6

x = 5/6 + √118/6 = 5 +√118 / 6

and

x = 5/6 - √118/6

x = 5- √118 / 6