We can use substitution.
We can substitute 2x + 3 for 'y' in the 2nd equation.
y = 3x + 5
2x + 3 = 3x + 5
Subtract 3 to both sides:
2x = 3x + 2
Subtract 3x to both sides:
-x = 2
Multiply -1 to both sides:
x = -2
Now we can plug this into any of the two equations to get our y-value:
y = 2x + 3
y = 2(-2) + 3
y = -4 + 3
y = -1
So our solution is (-2, -1)
Answer:
Step-by-step explanation:
four times the value of x = 4*x = 4x
two less than four times the value of x = 4x - 2
y= 4x - 2
Answer:
[4 + 1] *[7-2] =25
Step-by-step explanation:
[4 + 1] *[7-2] =25
We need to get to 25
What makes 25
5*5
4+1 =5
7-2 =5
5*5 =25
So we need brackets around 4+1 and around 7-2
Answer:
The short answer is there isn’t.
Start by writing each of these as an expression:
x * y = 60
x + y = 7
Next, solve each for the same variable; in this case, y:
(x * y) / x = 60 / x
.: y = 60 / x
(x + y) - x = 7 - x
.: y = 7 - x
Next, replace y of the second expression to the first
y = 60 / x & y = 7 - x
.: 7 - x = 60 / x
Now, solve for x:
(7 - x) * x = (60 / x) * x
.: x * 7 - x^2 = 60
This is quadratic, so write it in the form of ax2 + bx + x = 0
(-1)x^2 + (7)x + (-60) = 0
.: a = -1, b = 7, c = -60
Finally solve for b:
x = (-b +- sqrt(b^2 - 4*a*c)) / 2a
.: x = (-7 +- sqrt(7^2 - 4*-1*-60)) / (2 * -1)
.: x = (-7 +- sqrt(49 - 240)) / -2
.: x = (-7 +- sqrt(-191)) / -2
The square root of a negative value is imaginary and thus there’s no real answer to this problem.
