Algebra practice question

Answer: 10

20 + 2b = 40 gives 2b = 20, so b = 10.

Common wrong answers

If you answered 8

8 divides 40 by 5.

If you answered 20

20 is 2b.

If you answered 30

30 solves 5a + 2b = 40 with a = 4 by treating 2b as b plus 20; check 20 + 2(30) = 80.

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?