Combine & Conquer
Simplify: 8x − 2y + x + x
10x − 2y
Simplify: 9x − 3x − 4
6x − 4
Simplify: 3(n + 6)
3n + 18
Evaluate 25 − k + v for k = 20 and v = 10
15
Simplify: 5a + 3b − 2a + 7b
3a + 10b
Simplify: 5x + x − 4
6x − 4
Simplify: 2(n + 6) + (n + 6)
3n + 18
Evaluate 5h + 6 for h = 4
26
Simplify: 6m − 4 + 2m + 9
8m + 5
Is 12x − 4 equivalent to 6x − 4? Test both by substituting x = 2, then decide.
No — 12(2)−4 = 20, but 6(2)−4 = 8; they're not equal, so not equivalent.
Simplify: 3 − 5(−3n + 5)
15n − 22
Evaluate 15n − 22 for n = 3
23
Simplify: −3y + 8y − 5 + 2
5y − 3
Brianna says Expression A (9x−3x−4), Expression B (12x−4), and Expression C (5x+x−4) are ALL equivalent because they each equal −4 when x = 0. What's wrong with her reasoning, and which expressions are actually equivalent?
Two expressions being equal for just ONE value of x doesn't prove they're equivalent — they must be equal for EVERY value of x. Expressions A and C both simplify to 6x−4, so they're truly equivalent. Expression B simplifies to 12x−4, which is NOT equivalent to the others.
Simplify: −2(4x − 5) + 3x
−5x + 10
Evaluate 8m + 5 for m = −2
−11