What are the approximate solutions of 5x2 − 7x = 1 rounded to the nearest hundredth? No real solutions x ≈ −0.65 and x ≈ 7.65 x ≈ −1.53 and x ≈ 0.13 x ≈ −0.13 and x ≈ 1.53
ok you should solve this using Quadratic equation. \[\huge 5x^2-7x-1=0\] here a=5,b=-7,c=-1
@rebecca1233 did you get it?
OK, quick and dirty, without a huge amount of calculation. The quadratic function opens upwards (leading coefficient positive) and the y-intercept is negative. That means there will be two distinct real roots, so the first answer out. The axis of symmetry for the graph is x=-b/2a=7/10, so the solutions have to be equal distance above and below that x value. The only one of your given answers that meets that specification is the last one.
Think about the way the graph looks, and you can narrow the field of possible solutions quickly. Of course, you can grind it out as shown very nicely by sami-21.
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