Respuesta :
QUESTION 1
The given system of equations is
[tex]3d - e = 7...eqn(1)[/tex]
[tex]d + e = 5...eqn(2)[/tex]
To solve by linear combination, we add equation (1) to equation (2) to get,
[tex]3d + d= 7 + 5[/tex]
[tex]4d = 12[/tex]
We divide through by 4 to obtain,
[tex]d = \frac{12}{4} [/tex]
[tex]d = 3[/tex]
We put d=3 into equation (2) to get,
[tex]3+ e = 5[/tex]
[tex]e = 5 - 3[/tex]
[tex]e = 2[/tex]
[tex] \boxed {The \: solution \: is \: (3, 2)}[/tex]
QUESTION 2
The given system is
4x + y = 5 ...eqn(1)
3x + y = 3 ...eqn(2)
To solve by linear combination, we subtract equation (2) from equation (1) to eliminate y from the equation.
This will give us,
[tex]4x - 3x = 5 - 3[/tex]
This implies that,
[tex]x = 2[/tex]
Put x=3 into equation (1) to get,
[tex]4(2) + y = 5[/tex]
[tex]8+ y = 5[/tex]
[tex]y = 5 - 8[/tex]
[tex]y = - 3[/tex]
The solution is
[tex](2,-3)[/tex]
QUESTION 3
We want to solve the system;
a – 2b = –2 ....eqn(1)
2a + 2b = 14...eqn(2)
by linear combination.
We need to add equation (1) to equation (2) to eliminate b.
This implies that,
[tex]2a + a = 14 + - 2[/tex]
Simplify,
[tex]3a = 12[/tex]
Divide both sides by 3 to get,
[tex]a = 4[/tex]
Put a=4 into equation (2) to obtain,
[tex]2(4) + 2b = 14[/tex]
[tex]8 + 2b = 14[/tex]
[tex]2b = 14 - 8[/tex]
[tex]2b = 6[/tex]
[tex]b = 3[/tex]
The ordered pair in the form (a, b) is
[tex](4,3)[/tex]
QUESTION 4
The given system of equations is
11x + 4y = 18 ...eqn(1)
3x + 4y = 2 ...eqn(2)
We subtract equation (2) from equation (1) to get,
[tex]11x - 3x = 18 - 2[/tex]
[tex]8x = 16[/tex]
[tex]x = 2[/tex]
Put x=2 into equation (2) to obtain,
[tex]3(2) + 4y = 2[/tex]
This implies that,
[tex]6 + 4y = 2[/tex]
[tex]4y = 2 - 6[/tex]
[tex]4y = - 4[/tex]
[tex]y=-1[/tex]
The correct answer is (2,-1).
QUESTION 5
The given system is ;
2d + e = 8...eqn1
d – e = 4...eqn2
We add the two equations to eliminate e.
This implies that,
[tex]2d + d = 8 + 4[/tex]
[tex]3d = 12[/tex]
We divide both sides by 3 to get,
[tex]d = 4[/tex]
We put d=4 into equation (2) to get,
[tex]4 - e = 4[/tex]
[tex] - e = 4 - 4[/tex]
[tex] - e = 0[/tex]
[tex]e = 0[/tex]
The solution is
[tex](4,0)[/tex]
The given system of equations is
[tex]3d - e = 7...eqn(1)[/tex]
[tex]d + e = 5...eqn(2)[/tex]
To solve by linear combination, we add equation (1) to equation (2) to get,
[tex]3d + d= 7 + 5[/tex]
[tex]4d = 12[/tex]
We divide through by 4 to obtain,
[tex]d = \frac{12}{4} [/tex]
[tex]d = 3[/tex]
We put d=3 into equation (2) to get,
[tex]3+ e = 5[/tex]
[tex]e = 5 - 3[/tex]
[tex]e = 2[/tex]
[tex] \boxed {The \: solution \: is \: (3, 2)}[/tex]
QUESTION 2
The given system is
4x + y = 5 ...eqn(1)
3x + y = 3 ...eqn(2)
To solve by linear combination, we subtract equation (2) from equation (1) to eliminate y from the equation.
This will give us,
[tex]4x - 3x = 5 - 3[/tex]
This implies that,
[tex]x = 2[/tex]
Put x=3 into equation (1) to get,
[tex]4(2) + y = 5[/tex]
[tex]8+ y = 5[/tex]
[tex]y = 5 - 8[/tex]
[tex]y = - 3[/tex]
The solution is
[tex](2,-3)[/tex]
QUESTION 3
We want to solve the system;
a – 2b = –2 ....eqn(1)
2a + 2b = 14...eqn(2)
by linear combination.
We need to add equation (1) to equation (2) to eliminate b.
This implies that,
[tex]2a + a = 14 + - 2[/tex]
Simplify,
[tex]3a = 12[/tex]
Divide both sides by 3 to get,
[tex]a = 4[/tex]
Put a=4 into equation (2) to obtain,
[tex]2(4) + 2b = 14[/tex]
[tex]8 + 2b = 14[/tex]
[tex]2b = 14 - 8[/tex]
[tex]2b = 6[/tex]
[tex]b = 3[/tex]
The ordered pair in the form (a, b) is
[tex](4,3)[/tex]
QUESTION 4
The given system of equations is
11x + 4y = 18 ...eqn(1)
3x + 4y = 2 ...eqn(2)
We subtract equation (2) from equation (1) to get,
[tex]11x - 3x = 18 - 2[/tex]
[tex]8x = 16[/tex]
[tex]x = 2[/tex]
Put x=2 into equation (2) to obtain,
[tex]3(2) + 4y = 2[/tex]
This implies that,
[tex]6 + 4y = 2[/tex]
[tex]4y = 2 - 6[/tex]
[tex]4y = - 4[/tex]
[tex]y=-1[/tex]
The correct answer is (2,-1).
QUESTION 5
The given system is ;
2d + e = 8...eqn1
d – e = 4...eqn2
We add the two equations to eliminate e.
This implies that,
[tex]2d + d = 8 + 4[/tex]
[tex]3d = 12[/tex]
We divide both sides by 3 to get,
[tex]d = 4[/tex]
We put d=4 into equation (2) to get,
[tex]4 - e = 4[/tex]
[tex] - e = 4 - 4[/tex]
[tex] - e = 0[/tex]
[tex]e = 0[/tex]
The solution is
[tex](4,0)[/tex]