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LETS USE THE PREVIOUS ADDITION PROBLEM BUT CHANGE IT TO A SUBTRACTION
PROBLEM:

(2r^{4} + 3r^{3} - r^{2} + 5r + 4)
- (3r^{4} + 4r^{2} -2r - 7) = (2r^{4} + 3r^{3} - r^{2} + 5r + 4)
+ (-3r^{4} - 4r^{2} + 2r + 7)

In algebra we change subtraction problems to addition problems by changing the

SUBTRACTION SIGN - to an ADDITION SIGN + and then change the sign of every term that

immediately follows the subtration sign. Then proceed as if
it is an addition problem by combining like terms.

2r^{4} + 3r^{3} - r^{2} + 5r + 4
+ (-3r^{4} ) + (- 4r^{2} ) + 2r + 7 = 2r^{4}
+ (-3r^{4} ) + 3r^{3} - r^{2} + (- 4r^{2} ) + 5r
+ 2r + 7 + 4 = -r^{4} + 3r^{3} -
5r^{2} + 7r + 11
Try these:

(4t^{3} + 2t^{2} - 7t + 5) -
(5t^{4} + 3t^{3} + 4t - 7)
answer
(5p^{4} - 3p^{2} + 2p) - (2p^{3 } - 4p^{2}
+ 4p - 6) answer
return