Two students in Mrs. Johnson's preschool class are stacking blocks, one on top of the other. Sydney's blocks are 4 cm high, and
Maddy's blocks are 9 cm high. How tall will their stacks be when they are the same height for the first time? Do NOT write "cm" -- only type the number.
Ooh so the directions tell us what we need to find the entire line, which is made up of FH. so just add GH (15) and FG (6) together to find FH. so that is 21. FH=21.