Solve the system of equations.
7x+10y=36
y=2x+9
x =
y =

Step-by-step explanation:

Substitute the y in the 1st equation with the 2nd equation.

7x + 10(2x + 9) = 36

7x + 20x + 90 = 36

27x + 90 = 36

3x + 10 = 4

3x = -6

x = -2

So now we can find y.

y = 2x + 9 = 2(-2) + 9 = (-4) + 9 = 5.

So x = -2, y = 5.

0.02

step-by-step explanation:

time of 9 192 631 770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom at 0 k (but other seconds are sometimes used in astronomy)