Answer:
7 is a solution.
Step-by-step explanation:
Step 1: Write equation
5x + 7 = 42
Step 2: Solve for <em>x</em>
- Subtract 7 on both sides: 5x = 35
- Divide both sides by 5: x =7
Answer:
A.is the best answer I think

The property that justifies multiplying through eqn(2) by -2 is;
the rationalization to align the coefficients of x in both equations with a view to eliminating the terms in x.
Answer:
45 horseshoe crabs and 45 sea stars
Step-by-step explanation:
The aquarium initially contained x crabs and x sea stars.
"After 15 horseshoe crabs and 27 sea stars are removed the ratio of horseshoe crabs to sea stars is 5:3"
(x-15):(x-27) = 5:3
(x-15)/(x-27) = 5/3
3(x-15) = 5(x-27)
3x-45 = 5x-135
90 = 2x
x = 45