A linear equation has the variable to the first power. Undo addition or subtraction before multiplication, doing the same thing to both sides. You can also enter the original equation as a Desmos regression to find the unknown. The trap is reporting the value of a multiple of instead of itself.
Hints
- Hint 1
The is applied after is doubled. To undo that subtraction, add to both sides so they stay equal. What value does that give you for ?
- Hint 2
The coefficient is the number multiplying ; here it's . Knowing is not yet knowing . Divide by , or enter the original equation in Desmos using as the unknown.
Step-by-step
Undo the subtraction, then find
Step 1Get by itself
Add to both sides to undo the . Doing the same thing to both sides keeps the equation equal.
That's the value of twice , not .
- Step 2
Find the value of
Type the original equation in Desmos as . Desmos uses as the unknown to solve for and to match the two sides. Under PARAMETERS, it shows . So the value of that satisfies the equation is . Choice B.