A linear equation has an unknown with no powers higher than . For an equation with one unknown, a Desmos regression can find its value. Then check the expression the question asks for: if it asks for a multiple of the unknown, entering the unknown alone stops one move too soon.
Hints
- Hint 1
A solution is a value of that makes both sides of an equation equal. Find that value first, but check the question’s last words before entering it as your answer.
- Hint 2
In Desmos, replacing with and with tells the calculator to find a number that makes the sides match. Once it finds , what does tell you to do?
Step-by-step
Solve, then evaluate
Step 1Find the value of
A regression finds a number that makes both sides match. Type in Desmos: change to and to so Desmos solves instead of graphing. Under PARAMETERS, it shows . So you have found the value of , not yet the value asked for.
- Step 2
Find the requested value
Because means twice , use the value you found for to evaluate the requested expression. Type under the regression; Desmos prints . So the value of is . Grid in 6.