Hello!
4x - 9y = 20
2x - 6y = 16
You first need one of the variables have the same coefficient
We can do this by multiplying the second equation by 2
4x - 12y = 32
Subtract the equations to get rid of x
4x - 9y = 20
4x - 12y = 32
3y = -12
Divide both sides by 3
y = -4
Put y into one of the original equations
2x - 6(-4) = 16
Multiply
2x - -24 = 16
We you subtract a negative it is the same as addding
2x + 24 = 16
Subtract 24 from both sides
2x = -8
Divide both sides by 2
x = -4
The answers are x = -4 and y = -4
Hope this helps!
Step-by-step explanation:
10 -3 10+3*-3= 12 x=10-8=6
Answer:
T = 3.5 hours
Step-by-step explanation:
this is a rate problem.
an experienced surveyor takes 7 hours to survey a roadbed
an apprentice surveyor takes 9 hours to survey a roadbed
the rate of the experienced surveyor =
the rate of the apprentice surveyor = 
if the two work together , 
T = 
T = 3.5 hours
Answer:
572.1 gm will be left
Step-by-step explanation:
seven days of decay to find how much is still there on the 8th day
1400 ( 1 - .12)^7 =