Question

(2r-7)(5r-6)solve this quadratic equation in any of the three methods​

Answer 1

Answer:

r = 6/5 or r = 7/2

Step-by-step explanation:

You can do luke this

(2r - 7) ( 5r - 6)

= (2r - 7) = 0

2r = 7

r = 7/2

(5r - 6) = 0

5r = 6

r = 6/5

Answer 2

hi mate,

(2r-7)(5r-6)=0

We multiply parentheses ..

(+10r^2-12r-35r+42)=0

We get rid of parentheses

10r^2-12r-35r+42=0

We add all the numbers together, and all the variables

10r^2-47r+42=0

a = 10; b = -47; c = +42;

Δ = b2-4ac

Δ = -472-4·10·42

Δ = 529

The delta value is higher than zero, so the equation has two solutions

We use following formulas to calculate our solutions:

r1=−b−Δ√2ar2=−b+Δ√2a

Δ−−√=529−−−√=23

r1=−b−Δ√2a=−(−47)−232∗10=2420=1+1/5

r2=−b+Δ√2a=−(−47)+232∗10=7020=3+1/2

i hope it helps you.