Question
Solve the system: x + 2y = 13 3x − y =
5 What is the value of 2x + y?Solution
ATQ, From x + 2y = 13 ⇒ x = 13 − 2y Substitute into 3x − y = 5: 3(13 − 2y) − y = 5 39 − 6y − y = 5 39 − 7y = 5 ⇒ 7y = 34 ⇒ y = 34/7 Then x = 13 − 2(34/7) = 13 − 68/7 = (91 − 68)/7 = 23/7 2x + y = 2(23/7) + 34/7 = (46 + 34)/7 = 80/7
If “ A ” denotes “added to”, “ B ” denotes “divided by”, “ C ” denotes “multiplied by” and “ D ” denotes “subtracted from�...
If ‘–‘ means ‘addition’, ‘+’ means ‘subtraction’, ‘÷ ‘ means ‘multiplication‘ and ‘×’ means ‘division’ , then find t...
What will be the value of expression if the signs ‘(x)’ and ‘(+)’ are interchanged?
728 ÷ 13 x 20 ÷ 4 + 8 – 9
If + means ÷, × means +, ÷ means – and – means ×, then find the value of 48 × 35 – 5 + 7 ÷ 7 – 9
...Select the correct combination of mathematical signs that can sequentially replace the “@” sign and balance the following equation.
16@5@4@2@...
If '-' means '÷', '+' means ' X ', '÷' means '-' and ' X ' means '+', then what is the value of the following expression?
540 - 18 + 2 X 56 ...
If '@' means ' X ', '$' means '-', '#' means '÷', and '%' means '+', then what is the value of the expression: [75 % {(169 $ 15) # 11} @ 8]
Select the correct combination of mathematical signs to replace the '*' signs and to balance the given equation.
169 * 13 * 30 * 12 * 4 * 18 = 85
Select the correct combination of mathematical signs that can sequentially replace the * signs and balance the given equation.
128 * 4 * 12 * 3 * 8 = 20
If ‘P’ means (×), ‘Q’ means (÷), ‘R’ means (-), and ‘S’ means (+), then what is the value of the expression:
54 Q 6 S 14 P 14 R...
