please help me.. answer this question

1.
If a baseball is batted at an angle of 35 degree to the ground, the distance the ball travels can be estimated using the equation d=0.0034s^2+0.009s+0.3, where s is the speed, in kilometres per hour, and h is the distance flown, in metres. At what speed does the batter need to hit the ball in order to have a hoe run where the ball flies 125 m ? Round to he nearest tenth

You are given a formula which tells you the distance d the ball travels, when you input any particular speed s into the formula.

In this case, though, you know that you need the distance d to be 125, and you need to determine the speed s which will achieve that distance. In other words, you have

125 =

and you need to find the value(s) of s which make this true. An efficient way to do this is to first put it into standard form

(125 deducted from both sides)

and then use the quadratic formula (which you'll find in your book) to solve for s. Be aware that in many cases, a quadratic equation such as this one has two solutions, or roots, one of which might be a negative value. In a problem derived from a physical, real-world scenario like this one, you typically disregard the negative solution.