Solve 7r^2 9r-10 - ScanMath

Question

Simplify the expression

63 r^{3} - 10

Evaluate

7 r^{2} \times 9 r - 10

Solution

More Steps

Evaluate

7 r^{2} \times 9 r

Multiply the terms

63 r^{2} \times r

Multiply the terms with the same base by adding their exponents

63 r^{2 + 1}

Add the numbers

63 r^{3}

63 r^{3} - 10

Show Solution

r = \frac{3 1470}{21}

Alternative Form

r \approx 0.541444

Evaluate

7 r^{2} \times 9 r - 10

To find the roots of the expression,set the expression equal to 0

7 r^{2} \times 9 r - 10 = 0

Multiply

More Steps

Multiply the terms

7 r^{2} \times 9 r

Multiply the terms

63 r^{2} \times r

Multiply the terms with the same base by adding their exponents

63 r^{2 + 1}

Add the numbers

63 r^{3}

63 r^{3} - 10 = 0

Move the constant to the right-hand side and change its sign

63 r^{3} = 0 + 10

Removing 0 doesn't change the value,so remove it from the expression

63 r^{3} = 10

Divide both sides

\frac{63 r ^{3}}{63} = \frac{10}{63}

Divide the numbers

r^{3} = \frac{10}{63}

Take the 3 -th root on both sides of the equation

3 r^{3} = 3 \frac{10}{63}

Calculate

r = 3 \frac{10}{63}

Solution

More Steps

Evaluate

3 \frac{10}{63}

To take a root of a fraction,take the root of the numerator and denominator separately

\frac{3 10}{3 63}

Multiply by the Conjugate

\frac{3 10 \times 3 6 3 ^{2}}{3 63 \times 3 6 3 ^{2}}

Simplify

\frac{3 10 \times 3 3 147}{3 63 \times 3 6 3 ^{2}}

Multiply the numbers

More Steps

Evaluate

310 \times 33147

Multiply the terms

31470 \times 3

Use the commutative property to reorder the terms

331470

\frac{3 3 1470}{3 63 \times 3 6 3 ^{2}}

Multiply the numbers

More Steps

Evaluate

363 \times 3 6 3^{2}

The product of roots with the same index is equal to the root of the product

3 63 \times 6 3^{2}

Calculate the product

3 6 3^{3}

Reduce the index of the radical and exponent with 3

63

\frac{3 3 1470}{63}

Cancel out the common factor 3

\frac{3 1470}{21}

r = \frac{3 1470}{21}

Alternative Form

r \approx 0.541444

Show Solution