I think that the answer is #2.
Alright, lets get started.
Justin is asked to solve the linear equations using elimination method.
By using elimination method means we have to multiply some numbers in our given equations in such a way that the co-efficient of x or y become same in both equations so that we could add or subtract them to cancel one of the term either x or y.
So, given equations are :


See we have 5x in first equation and -20x in second equation.
So, we try to change 5x into 20 x by multiplying it with 4, both of the equations will have 20 x in common
Lets multiply 4 in first equation


Now both equations could be added and 20 x will be cancelled out and we could easily find the value of y then solve for x.
So, Justin should try to change 5 so that it will be cancels, so option B : Answer
Hope it will help :)
Answer: 49x^2=-21x-2 quadratic functions -1/7and -2/7
Step-by-step explanation:
Quadratic function:
In elementary algebra, the quadratic formula is a formula that provides the solution to a quadratic equation. There are other ways of solving a quadratic equation instead of using the quadratic formula, such as factoring, completing the square, graphing and others.
Move terms to the left side
49
=-21x-2
49
-(-21x-2) =0
Distribute
49
-(-21x-2) =0
49
+21x+2=0
Use the quadratic formula
x=(-b±√
-4ac ) / 2a
Once in standard form, identify a, b, and c from the original equation and plug them into the quadratic formula.
49
+21x+2=0
let, a=49
b=21
c=2
Replace with values in this equation
X=(-b±√
-4ac ) / 2a
Simplify
Evaluate the exponent
Multiply the numbers
Subtract the numbers
Evaluate the square root
Multiply the numbers
x=(-21±7) /98
Separate the equations
To solve for the unknown variable, separate into two equations: one with a plus and the other with a minus.Separate
x=(-21+7) /98
x=(-21-7) /98
Solve
Rearrange and isolate the variable to find each solution
x=-1/7
x=-2/7
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Answer:
d
Step-by-step explanation:
This is equivalent to:
(2.2533/2.59)(10^8/10^4)
(0.87)(10^4) which is:
0.87X10^4 which is equal to:
0.87X10000 which is equal to:
8.7X1000 and since 1000=10^3 we can say:
8.7X10^3