A motorist travels for 3 hours at a certain speed and then increase his speed by 10 km for the next 4 hours If he travels 335 km altogether, Find his speed for the First 3 hours

See the answer below.

Step-by-step explanation:

We know that:  

So, using the given data, we can write an equation for the total distance travelled as:

Best Regards!

answer: 12

step-by-step explanation:

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4