Answer:
x = -3.5
Step-by-step explanation:
Simplifying
0.4x + 2.9 = 1.5
Reorder the terms:
2.9 + 0.4x = 1.5
Solving
2.9 + 0.4x = 1.5
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-2.9' to each side of the equation.
2.9 + -2.9 + 0.4x = 1.5 + -2.9
Combine like terms: 2.9 + -2.9 = 0.0
0.0 + 0.4x = 1.5 + -2.9
0.4x = 1.5 + -2.9
Combine like terms: 1.5 + -2.9 = -1.4
0.4x = -1.4
Divide each side by '0.4'.
x = -3.5
Simplifying
x = -3.5
There is no table so I cannot help you other than to say
to find the answer multiply the time swimming of each participating swimmer by .7 and you shall get your time.
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