Asked by johnnie
please help im lost the instructions are to solve by using thee quadriatic formula and prove your answers are correct but i don't know how can someone show mw step by step how to do this so i can do my homework
x^2-3x+4=0
x^2-3x+4=0
Answers
Answered by
Steve
just plug the numbers into the formula:
x = (3±√(3^2-4*1*4))/2
= (3±√-7)/2
= 3/2 ±√7/2 i
check:
(3/2+√7/2 i)^2 - 3(3/2+√7/2 i) + 4
= 9/4 + 3√7/2 i - 7/4 - 9/2 - 3√7/2 i + 4
= 0
same for (3-√7 i)/2
x = (3±√(3^2-4*1*4))/2
= (3±√-7)/2
= 3/2 ±√7/2 i
check:
(3/2+√7/2 i)^2 - 3(3/2+√7/2 i) + 4
= 9/4 + 3√7/2 i - 7/4 - 9/2 - 3√7/2 i + 4
= 0
same for (3-√7 i)/2