Answer: The answer is 1/3
<span>If y varies directly with x, the formula of the equation is y=ax, where a is a constant.
y=ax
(21)=a(7)
a=3
y=ax
y=(3)(-1.66)
y=-4.98, x=-1.66
If y varies inversely with x, the formula of the equation is y=a/x, where a is a constant
y=a/x
9=a/2.5
a=22.5
y=22.5/x
y=22.5/-0.6
y=-37.5
I hope this helped! =)
I hope you didn't mind but I got this from a website called: answers.yahoo.com but I got your answer.
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Answer:
the answer to this question is 52.18
Let x = amount of 45% antifreezeLet y = amount of 70% antifreeze EQUATION 1: x + y = 150 (total of 150 gallons mixed) EQUATION 2: .45x + .75y = .55(x + y) Simplify and solve the system of equations Multiply second equation by 100 on both sides to remove the decimals 45x + 75y = 55(x + y) Combine like terms 45x + 75y = 55x + 55y 45x - 55x + 75y - 55y = 0 -10x + 20y = 0 Now we have the following system of equations: x + y = 150 -10x + 20y = 0 Multiply the first equation by -10 to get opposite coefficients for x; add the equations to eliminate x 10x + 10y = 1500 -10x + 20y = 0 ------------------------------ 30y = 1500 Solve for y 30y = 1500 y = 50 Since the total mixed gallons is 150, x = 150 - 50 = 100 So we need 100 gallons of the 45% antifreeze and 50 gallons of the 70% antifreeze
Answer:
120c²d - 1200cd² -10c + 100d
Step-by-step explanation:
We will first of all evalute inide the bracket then we expand it.
(10c6d-5)(2c-5d4)
=(60cd-5)(2c-20d)
= 60cd*2c -60cd*20d -5*2c +5*20d
= 120c²d - 1200cd² -10c + 100d