All the numbers in the first equation have a common factor of 2. Removing that gives
.. x +4y = 6
making it easy to solve for x
.. x = 6 -4y
My choice would be to solve for x using the first equation.
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On second thought, it might actually be easier to solve either equation for 8y. That term then directly substitutes into the other equation (equivalent to adding the two equations).
.. 8y = 3x -11 . . . . . from the second equation
.. 2x +(3x -11) = 12 . . . substituting into the first equation
.. 5x = 23 . . . . . . . . . . collect terms, add 11 (what you would get by adding the equations in the first place)
.. x = 4.6
.. y = (3*4.6 -11)/8 = 0.35
Answer:
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Step-by-step explanation:
Answer:
h = 24 cm
Step-by-step explanation:
The formula for area of a triangle is
A = (1/2)bh where b is the base and h is the height.
We are told that the base is 5 times the height, this translates to
b = 5h, so we can rewrite our formula to
A = (1/2)(5h)(h) or
A = (1/2)5h²
We are given A = 1,440, so plug that in and solve for h...
1,440 = (1/2)5h²
2,880 = 5h² (multiply both sides by 2 to get rid of the fraction)
576 = h² (divide both sides by 5 to get the h value by itself)
24 = h (take the square root of both sides)
Distribute to eliminate the parenthesis
x^2 + 2x + 6x + 12 = 60
Combine like terms
x^2 + 8x + 12 = 60
Subtract 60 from both sides
x^2 + 8x - 48 = 0
Factor the equation
(x+12)(x-4)=0
x+12=0
x+4=0
x= -12 and -4