Simplify the following expression 4(x+3)-12+x

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years

Given the system of equations presented here: 2x + 4y = 14 4x + y = 20 which of the following actions creates an equivalent system such that, when combined with the other equation, one of the variables is eliminated? multiply the second equation by â’4 to get â’16x â’ 4y = â’80 multiply the second equation by â’1 to get â’4x â’ y = â’20 multiply the first equation by 2 to get 4x + 8y = 28 multiply the first equation by â’1 to get â’2x â’ 4y = â’14

What is the measure of angle x? a.101 b.158 c.44 d.79