Solve for x. Give answers to 3 decimal places.
x(2x – 5) = 13
thankyou thankyou thankyou!!
2007-06-12 00:58:42 · 3 answers · asked by mm_uk_2005 2 in Education & Reference ➔ Homework Help
2x^-5x=13
2x^-5x-13=0
a=2, b=-5, c=-13
x1,2=(-b±√b^-4ac / 2a
=(5 ± √(-5)^ - 4. 2. (-13)) / 2. 2
=(5 ± √(25+104)) / 4
=(5± √129) / 4
x1 =(5+√129) / 4 V x2 =(5-√129) / 4
NB: V means 'or'
2007-06-12 02:07:05 · answer #1 · answered by MetZ 2 · 0⤊ 0⤋
x(2x - 5) = 13
multiply x through the left side
2x^2 - 5x = 13
subtract 13 from both sides so that one side is equal to zero
2x^2 - 5x - 13 = 0
figure out the quadratic
x=(5 +/- â(-5^2 - 4*2*-13))/(2*2)
x=(5 +/- â129)/4
x=(5 + 11.358)/4 or (5 - 11.358)/4
x=(16.358)/4 or (-6.358)/4
x=4.090 or -1.590
2007-06-12 08:25:23 · answer #2 · answered by jiffyville 2 · 0⤊ 0⤋
x(2x – 5) = 13
Expand
2x² - 5x - 13 = 0
Solve with quadratic formula
x = (-b ± â(b² - 4ac))/2a
x = (5 ± â(25 + 104))/4
x = (5 ± â(129))/4
x = (5 ± 11.3578)/4
x = 4.089, x = -1.589
.
2007-06-12 08:15:23 · answer #3 · answered by Robert L 7 · 0⤊ 0⤋