1. The product of a number and four more than the number is 12 find the two numbers 2. The length of rectangle is 1 cm less than three times the width. If the are of the rectangle is 30 cm^2, find the dimensions of the rectangle

3. You throw a rock straight up form a cliff that was 24 ft above the water. If the weight of the rock, h, in feet, after t seconds is given by the equation h =-16t^2+20t+24, how long will it take for the rock to hit the water? (hint: set h to 0 and solve with the quadratic formula)

the circle one

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

answer: do we write it

step-by-step explanation: