Question

solve the ticked quadratic equation word problem ​

Answer 1

Step-by-step explanation:

6. Let the initial average speed of a car be X km/h

For this speed time required to cover 200km will be T1= 200/X -----eq. 1

now speed is increased by 5 km/h and so time is decreased by 2 hours

so new speed will be=(X + 5) km/h

by this speed time required to cover the 200km distance T2= 200/(X + 5)......EQ.2

T2= (T1 -2) HOUR ------EQ..3

PUT THE VALUE OF EQ. 3 INTO EQ.2

WE GET,

T1 - 2 = 200/(X + 5)

now put the value of T1 from eq.1

200/X - 2=200/(X+ 5)

By solving this we get

quadratic equation, x^2 + 5x - 500= 0

( x+25)(x-20)=0

so x= 20 is possible

so our answer would be 20km/h

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9. same as 6 just convert minutes into hours

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