Solve the following system of equations:
−2x + y = 1
−4x + y = −1
a- (3, 1)
b- (−1, 3)
c- (−1, −3)
d- (1, 3)

x = 1 , y = 3 thus D: is your answer

Step-by-step explanation:

Solve the following system:

{y - 2 x = 1 | (equation 1)

y - 4 x = -1 | (equation 2)

Swap equation 1 with equation 2:

{-(4 x) + y = -1 | (equation 1)

-(2 x) + y = 1 | (equation 2)

Subtract 1/2 × (equation 1) from equation 2:

{-(4 x) + y = -1 | (equation 1)

0 x+y/2 = 3/2 | (equation 2)

Multiply equation 2 by 2:

{-(4 x) + y = -1 | (equation 1)

0 x+y = 3 | (equation 2)

Subtract equation 2 from equation 1:

{-(4 x)+0 y = -4 | (equation 1)

0 x+y = 3 | (equation 2)

Divide equation 1 by -4:

{x+0 y = 1 | (equation 1)

0 x+y = 3 | (equation 2)

Collect results:

{x = 1 , y = 3

x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x

step-by-step explanation:

last month maria hiked the 5-mile mountain trail a number of times and she hiked the 10-mile canal trail several times. let x represent the number of times she hiked the 5-mile trail, and let y represent the number of times she hiked the 10-mile trail. if she hiked a total of 90 miles, which equation can be used to find the number of times maria hiked each trail? x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204