Section 5.3 Deliberate Practice: Substitute and Solve
Algebra is a skill, which means it requires practice to become proficient. But it will take more than rote repetition to get there. Deliberate practice is the thoughtful repetition of a task. For each of these sections, you will be given a list of specific skills or ideas to focus on as you practice thinking through the problems.
Focus on these skills:
Write the original equation.
Use parentheses with the substitution.
Be careful with negative signs and the distributive property.
Present your work legibly.
Worksheet Worksheet
Instructions: Substitute the first equation into the second equation, then solve for the remaining variable.
1.
\(y = 3x + 4; \quad 2x + 3y = -6\)
2.
\(a = 3b - 2; \quad 4a - 3b = 7\)
3.
\(m = n - 4; \quad -2m + 3m - 5 = -8\)
4.
\(t = -2s + 3; \quad 3s - 2t + 7 = 7\)
5.
\(b = -3a + 1; \quad 4a - b - 4 = 4\)
6.
\(x = - y + 3; \quad -3x - 4y + 6 = 0\)
7.
\(u = 2v - 4; \quad 3u + 4v - 3 = -2u - 5\)
8.
\(r = 3s + 1; \quad -r + 3s - 3 = 4r - 3s + 7\)
9.
\(x = -2y + 3; \quad 2x - y + 4 = x - 3y - 6\)
10.
\(n = -3m - 4; \quad 2m - 3n - 1 = -2m + 4n + 5\)