How to solve this? answer #maths #form4

x = 5

Step-by-step explanation:

Distance travelled in 2 secs at a speed of x ms-1

= speed * time = 2x m.

Distance travelled at  (3x - 14) ms-1 for x secs

=  x(2x - 14) m.

Therefore  2x + x(3x - 14) = 15

3x^2 - 12x - 15 = 0

x^2 - 4x - 5 = 0

( x - 5)(x + 1) = 0

x = 5, -1

As  x cannot be negative it must be 5

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents

if x = 1, then the answer is 3.5