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How do you solve the following linear system #-4x +9y = 5 , x - 4y = -3 #?

Answer 1

Avery Alexander

#x=1; y=1#

First, let's obtain x in the second equation: #x=4y-3#

then let's substitute its value in the first one: #-4(4y-3)+9y=5#

then, by simplifying: #-16y+12+9y=5# #-16y+9y=-12+5# #-7y=-7# #y=1#

and now let's substitute the value of y in #x=4y-3#

so that #x=4*1-3# #x=1#

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Answer 2

Ethan Adkins

To solve the linear system -4x + 9y = 5 and x - 4y = -3, you can use the method of substitution or elimination. Here, we'll use the substitution method:

From the second equation, we can express x in terms of y as x = 4y - 3.

Substitute this expression for x into the first equation: -4(4y - 3) + 9y = 5 -16y + 12 + 9y = 5 -7y = -7 y = 1

Now that we have the value of y, we can substitute it back into the equation x = 4y - 3 to find the value of x: x = 4(1) - 3 x = 4 - 3 x = 1

Therefore, the solution to the linear system is x = 1 and y = 1.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.