Question Video: Subtracting Algebraic Expressions Mathematics • First Year of Preparatory School

Video Transcript

Subtract seven 𝑦 plus 𝑧 squared minus three 𝑥 cubed from six 𝑥 cubed plus five 𝑧 squared minus eight 𝑦.

In order to subtract these two expressions, we need to group or collect the like terms. Firstly, we can group the 𝑥 cubed terms. Six 𝑥 cubed minus negative three 𝑥 cubed, this is equal to nine 𝑥 cubed as six minus negative three is equal to nine.

Next, we can group the 𝑦 terms. Negative eight 𝑦 minus seven 𝑦, this is equal to negative 15 𝑦 as negative eight minus seven is equal to negative 15.

Finally, we need to group the 𝑧 or 𝑧 squared terms. Five 𝑧 squared minus 𝑧 squared, this is equal to four 𝑧 squared as five minus positive one is equal to four.

This means that our answer when we subtract seven 𝑦 plus 𝑧 squared minus three 𝑥 cubed from six 𝑥 cubed plus five 𝑧 squared minus eight 𝑦 is equal to nine 𝑥 cubed minus 15 𝑦 plus four 𝑧 squared.