Get the unknown alone by removing terms and factors from both sides, collect unknowns on one side, and always check your answer.
Preview · progress not saved — Chapter 1 is free
Get the unknown term alone, then the unknown itself.
Solve and check an equation with a negative term.
Problem. Solve 11y + (−5) = 61. (Textbook p. 171)
Equations with the unknown on one side.
Solve 3x − 10 = 35. (p. 172)
First bring all the unknown terms to one side.
The unknown is on both sides. Just as we removed sacks from both plates, subtract 4y from both sides:
6y + 7 − 4y = 4y + 21 − 4y, so 2y + 7 = 21.
Solving 3u − 7 = 2u + 3, 4(m + 6) − 8 = 2m − 4 and 5s = 3s.
Problem. Solve Figure it Out Q1 (b), (c) and (d). (Textbook p. 172)
Complete the steps for equations with unknowns on both sides.
(e) k + 8 = 12 − k. Add k to both sides: 2k + 8 = . Subtract 8: 2k = . So k = .
(f) 7m = m − 3. Subtract m from both sides: m = −3. So m = .
(g) 3n = 10 + n. Subtract n: 2n = . So n = .
Frame an equation that no number can satisfy.
Figure it Out, Textbook p. 172, Q2. Frame an equation that has no solution.
Hint: 4 more than a number and 5 more than a number can never be equal!
Write your equation and explain why no value of the letter can make LHS = RHS.
What happens when you remove the unknown terms from both sides?