True or false: for the set of all negative integers, ∃x (x + 1 < - x)

Two cyclists 84 miles apart start riding toward each other at the same. one cycles 2 times as fast as the other. if they meet 4 hours later, what is the speed (in mi/h) of the faster cyclist?

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

Which shows the correct substitution of the values a,b and c from the equation 1=-2x+3x^2+1