Yolanda is saving for a new cell phone. So far she has saved $90 from her babysitting jobs. She calculated that this is 45% of the total amount that she needs to buy the phone. What is the total cost of the phone?

t = 3

step-by-step explanation:

put t = 3 in this expression :

(3²-1)(3²-2)(3² - 3)(3² - 4) = 8×7×6×5 = 56×30 = 1680

5x+10 is the correct one

hope this

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!