Algebra practice question

Answer: 11

Adding the equations gives 4x = 12, so x = 3 and y = 4. Then x + 2y = 11.

Common wrong answers

If you answered 3

3 is x alone.

If you answered 7

7 is x + y.

If you answered 10

10 is 2y + 2, a slip.

More Algebra questions

• Easy–Medium
  A line passes through the points (0, 3) and (2, 7). What is the slope of the line?
• Easy–Medium
  A gym charges a $25 one-time signup fee plus $15 per month. Which equation gives the total cost C, in dollars,…
• Easy–Medium
  If 5(x − 2) = 3x + 4, what is the value of x?
• Easy–Medium
  A taxi charges a $3.50 base fare plus $2.25 per mile. If a ride costs $19.25 total, how many miles was the rid…
• Easy–Medium
  The equation of a line is 3x + 2y = 12. What is the y-coordinate of the point where the line crosses the y-axi…
• Easy–Medium
  A line in the xy-plane passes through the points (1, 5) and (4, 11). What is the y-intercept of the line?