SAT Practice Questions (Digital) — All Questions

If 3x - 5 = 16, what is the value of x?

• a.3
• b.5
• c.7✓
• d.9

Add 5 to both sides: 3x = 21. Divide by 3: x = 7. Check: 3(7) - 5 = 21 - 5 = 16.

A line passes through the point (0, 2) and has a slope of 3. What is the y-value when x = 4?

• a.6
• b.10
• c.12
• d.14✓

The line is y = 3x + 2 (slope 3, y-intercept 2). At x = 4: y = 3(4) + 2 = 12 + 2 = 14.

If 2x + 3y = 12 and x = 3, what is the value of y?

• a.1
• b.2✓
• c.3
• d.4

Substitute x = 3: 2(3) + 3y = 12, so 6 + 3y = 12. Then 3y = 6 and y = 2.

Given the system x + y = 10 and x - y = 4, what is the value of x?

• a.3
• b.5
• c.7✓
• d.8

Add the two equations: (x + y) + (x - y) = 10 + 4, so 2x = 14 and x = 7. (Then y = 3.)

If f(x) = 2x + 1, what is f(5)?

• a.11✓
• b.10
• c.12
• d.6

Substitute x = 5: f(5) = 2(5) + 1 = 10 + 1 = 11.

Solve for x: 4(x + 1) = 2x + 10.

• a.2
• b.3✓
• c.4
• d.5

Distribute: 4x + 4 = 2x + 10. Subtract 2x: 2x + 4 = 10. Subtract 4: 2x = 6, so x = 3. Check: 4(3 + 1) = 16 and 2(3) + 10 = 16.