ethan can swim 25 meters of backstroke in 19.2 seconds. how long will it take him to swim 100 meters?

76.8 seconds

Step-by-step explanation:

25 meters is 1/4 of 100 meters. Multiply the time for 25 meters by 4 to get the time for 100 meters. Meters and time must be multiplied by the same number to get a correct result in a case like this.

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions

a) 7x=7

step-by-step explanation: