19651789
| Question | Answer |
| "a" is always the number before the x(squared) term "b" is always the number before the x term "c" is always the number with no x | quadratic equation example ------------------------------- • 2x(squared) + 2x - 5 = 0 a= 2 b= 2 c= -5 • x = -2 +/- (square root) 2(squared) - 4 X 2 X -5 __________________ 2 X 2 SIMPLIFY • -2 +/- (square root) 4 + 40 _________________ 4 SIMPLIFY • -2 +/- (square root) 44 _______________ 4 |
| Factorising ------------- •Find 2 numbers that add to make the number without x and multiply to make the number with x •write the number in brackets •take both brackets and take off the brackets •make both equations equal to x | example ---------- • x(squared) - 8x + 15 = 0 • (x - 3) (x - 5) = 0 • x - 5 = 0 x - 3 = o +5 +3 • x = 5 or x = 3 |
| complete the square -------------------- • make sure "a" = 1 (if not then make it 1) • bring "c" to the right side • add ( "b" ) (squared) -------------------- 2 • factorise • square root both sides • solve for x | example ----------- • x(squared) - 10x -2 • x(squared) - 10x = 2 • x(squared) - 10x + (10) (squared) _ 2 = 2 + (10) (squared) _ 2 simplify • x(squared) - 10x +25 = 2 + 25 simplify • x(squared) - 10x + 25 = 27 • (x - 5)(x - 5) = 27 • square root both sides • x - 5 = +/- (square root) 27 |
Want to create your own Flashcards for free with GoConqr? Learn more.