Answer:
<u>The solution of this system of equation is ( 3, - 8)</u>
Step-by-step explanation:
1. Let's solve the system of equations:
First equation:
x + 2y = - 13
x = - 13 - 2y
Second equation:
12x + 5y = -4
12 * (- 13 - 2y) + 5y = - 4 (Replacing x with - 13 - 2y)
-156 -24y + 5y = - 4
-24y + 5y = - 4 + 156 (Like terms)
-19y = 152
y = - 152/19
<u>y = -8</u> (Dividing by 19)
Solving x
x + 2y = -13
x + 2 (- 8 ) = - 13
x - 16 = - 13
x = - 13 + 16
<u>x = 3</u>
2. Proving that x = 3 and y = - 8 are correct:
12x + 5y = -4
12 * 3 + 5 * -8 = -4
36 - 40 = - 4
- 4 = - 4
<u>We proved that x = 3 and y = - 8 are correct</u>
Answer:
7A−(I + A)³
=7A−(1³ + A³ +3.I.A² +3.1².A)
=7A−(I+ A².A+3A² +34)
= 7A-(I+A.A+3A+34) (*: A² = A)
=7A-(I+ A² +6A)
= 7A-(I+A+64)
=7A-(1+7A)
=7A-I-7A
=-1
Answer:
Point D
Step-by-step explanation: