Answer:
B)
Step-by-step explanation:
225x^2 - 1=
(15x)^2 - 1^2=(*)
(15x-1)(15x+1)
A^2 - B^2 =(A-B)(A +B)............. (*)
Answer: The numbers are -3 and 2
Step-by-step explanation: Let x be the first number and y be the second number
then according to given statements the linear equations will be:
"Four times a number minus twice another number is -16"
"The sum of the two numbers is -1"
From equation 2:
Putting y = -x-1 in equation 1
Subtracting 2 from both sides
Dividing both sides by 6
Putting x = -3 in equation 2:
Hence,
The numbers are -3 and 2
Answer:
19
Step-by-step explanation:
12-n/7 = -1
Cross multiply
We have 12-n = -7
Collect like terms
12 + 7 = n
Therefore n = 19
Answer: F
Step-by-step explanation: 90/3.28 equals 27.4390244
Answer:
(½x+½y)²=6
Step-by-step explanation:
x^2 + y^2 = 14, xy=5
(A+B)^2=A^2 +2AB+B^2... (*)
(1/2x+1/2y)^2 =(*)
(1/2x)^2 +2(1/2x)(1/2y)+(1/2y)^2 =
1/4x^2 +1/2xy+1/4y^2=
1/4(x^2 +y^2) +1/2(xy)=
1/4*14+1/2*5=
14/4+5/2=
14/4+10/4=
24/4=6
let me know if I'm wrong.
