Answer:
noestiendo
Step-by-step explanation:
Answer:
Step-by-step explanation:
Given the simultaneous equation 2p - 3q = 4 and 3p + 2q = 9, to get the value of p and q we will use elimination method.
2p - 3q = 4 ...................... 1 * 3
3p + 2q = 9 ..................... 2 * 2
Multiplying equation 1 by 3 and 3 by 2:
6p - 9q = 12
6p + 4q = 18
Subtracting both equation
-9q-4q = 12-18
-13q = -6
q = -6/-13
q = 6/13
Substituting q = 6/13 into equation 2
2p - 3(6/13) = 4
2p - 18/13 = 4
2p = 4+18/13
2p = (52+18)/13
2p = 70/13
p = 70/26
p = 35/13
<em>Hence p = 35/13 and q = 6/13</em>
<em></em>
<em>b) </em>If if 223ₓ = 87 find x
Using the number base system and converting 223ₓ to base 2 will give us;
223ₓ = 2*x² + 2*x¹ + 3*x⁰
223ₓ = 2x²+2x+3
Substituting back into the equation, 2x²+2x+3 = 87
2x²+2x+3-87 = 0
2x²+2x-84 = 0
x²+x-42 = 0
On factorizing:
(x²+6x)-(7x-42) = 0
x(x+6)-7(x+6) = 0
(x+6)(x-7) = 0
x+6 = 0 and x-7 = 0
x = -6 and 7
<em>Hence the value of x is 7 (neglecting the negative value)</em>
According to your question, there are 2 unknown numbers mentioned.
Let the 2 unknown numbers be represented by the variables x & y, then
x is considered to be one of the numbers being more than y by the addition of 4, .ie.
x = 4 + y --- (1)
The sum of the 2 numbers is 60, i.e.
x + y = 60 --- (2)
To find the smaller number, we solve eqn (1) & (2) using the concept of substitution, i.e. substitute 4 + y for x in eqn (2), i.e.
4 + y + y = 60
4 + 2y = 60
2y = 60 - 4
2y = 56
y = 28 ...Ans.
Recall that x is more than y by 4, then 28 is the smaller number.
Answer:
7
Step-by-step explanation:
each way from 10 to 7 is 3 and 4 to 7 is 4
When you multiply or divide two positives or two negatives, the answer is positive.
72/9 = 8
-72/(-9) = 8
Correct answer: Choice D.
