Advertisements
Advertisements
Question
Two equal sides of an isosceles triangle are 5y – 2 and 4y + 9 units. The third side is 2y + 5 units. Find ‘y’ and the perimeter of the triangle.
Advertisements
Solution
Given that 5y – 2 & 4y + 9 are the equal sides of an isosceles triangle.
∴ The 2 sides are equal
⇒ 5y – 2 = 4y + 9
∴5y – 4y = 9 + 2 ...(by transposing)
∴ y = 11
∴ 1st side = 5y – 2 = 5 × 11 – 2 = 55 – 2 = 53
2nd side = 53
3rd side = 2y + 5 = 2 × 11 + 5 = 22 + 5 = 27
Perimeter is the sum of all 3 sides
∴ P = 53 + 53 + 27 = 133 units
APPEARS IN
RELATED QUESTIONS
Set up an equation in the following case:
Irfan says that he has 7 marbles more than five times the marbles Parmit has. Irfan has 37 marbles. (Take m to be the number of Parmit’s marbles.)
Different mathematical operations are given in the two rows below. Find out the number you get in each operation and make equations.
16 ÷ 2; 5 × 2; 9 + 4; 72 ÷ 3; 4 + 5; 8 × 3; 19 - 10; 10 - 2; 37 - 27; 6 + 7
Add 7xyz, − 5xyz, 9xyz, −8xyz
Write the following statement as an equation:
3 less than 4 times a number is 17.
Solve the following equation by the trial-and-error method: 11 + x = 19
Solve the following equation by the trial-and-error method: `x/3`= 4
The cost of 1 pen is Rs 16 and the cost of 1 pencil is Rs 5. What is the total cost of x pens and y pencils?
After 16 years, Seema will be three times as old as she is now. Find her present age.
Given Sara’s age today to be y years. Think of her age in the future or in the past. What will the following expression indicate?
y + 7, y − 3, `"y" + 4 1/2`, `"y" - 2 1/2`
Pick out the solution from the values given in the bracket next to each equation. Show that the other values do not satisfy the equation.
`"q"/2 = 7` (7, 2, 10, 14)
