Answer:
Step-by-step explanation:
The method of variable substitution is a way of solving a system of equations. It involves solving one equation for a variable and then substituting in the expression that represents the value of the solved variable into the other equation. After doing so, one can solve for the unknown variable and then backsolve for the other variable.
In this system, the second equation is already solved for (y), thus one can substitute that expression into the other equation in the system.
Now solve using inverse operations,
Backsolve to find the value of (y), substitute in the value of (x), and solve for the value of (y).
Substitute,
Solve,
Thus, the answer to this system of equations is the following, .
Answer:
2x = 70
Step-by-step explanation:
4x - 2x = 70
2x = 70
x = 70/2
x = 35
Answer:
2by5=,78
Step-by-step explanation:
if you 9thru7. into8 you get 2by 7
D: 27.47 cm. A=b×h÷2
6.7×8.2=54.94
54.94÷2=27.47 cm
hey what can I say except your welcome.
Answer:
Step-by-step explanation:
Solve Using the Quadratic Formula
4x^2 + 8x − 5 = 0
Use the quadratic formula to find the solutions.
−b ± √b^2 − 4 (ac)
-------------------------
2a
Substitute the values a = 4, b = 8, and c = −5 into the quadratic formula and solve for x.
−8 ± √82 − 4 ⋅ (4 ⋅ −5)
-------------------------
2 ⋅ 4
Simplify the numerator.
Raise 8 to the p ower of 2.
−8 ± √64 − 4 ⋅ 4 ⋅ −5
x= ---------------------------
2 ⋅ 4
Multiply −4 by 4.
−8 ± √64 − 16 ⋅ −5
x = -------------------------
2 ⋅ 4
Multiply −16 by −5.
−8 ± √64 + 80
x = -------------------
2 ⋅ 4
Add 64 and 80.
−8 ± √144
x = --------------
2 ⋅ 4
Rewrite 144 as 12^2.
−8 ± √122
x = ------------
2 ⋅ 4
Pull terms out from under the radical, assuming positive real numbers.
multiply 2 by 4
−8 ± 12
x= ------------
8
simplify
−2 ± 3
x= ---------
2
The final answer is the combination of both solutions.
x= 1/2, -5/2
Hope this helped!
