John had $21 to spend on 2 notebooks. After buying them he had $13. How much did each notebook cost?

How do I learn more about mathematics even though we usually do study island and its lesson are sometimes to much to take in ...

What is the value of k? 1/2k+6=4k-812k+6=4k-8

Which diagram has all the correct lines of reflections symmetry for the rectangle?

Subtract 3 hours, 50 minutes from 5 hours, 20 minutes. 2 hours, 20 minutes 1 hour, 40 minutes 1 hour, 30 minutes 2 hours, 30 minutes

Eliminating a disease suppose that in any given year, the number of cases of a disease is reduced by 20%.

Least to greatest 3/4, 0.7, 1/2, 0.1

Simplify the polynomial (-8*) + * + (-2)

Evaluate the expression below when y = - 3. 2y + 7 -4y - 10 A. -1 22 B. -13 2 C. 1 2 D. 1

A science teacher ordered $660 worth of microscopes and dissection kits for the new science lab. A total of 22 microscopes and 44 dissection kits were ordered. A microscope costs three times as much as a dissection kit.

The square root of a 100 is it a whole number or natural number