Solve 30*5+5a=0.9*30+0.9*5*(a-5)

$$30 \times 5 + 5 a = 0.9 \times 30 + 0.9 \times 5 \times ( a - 5 )$$

Solve for a

$$a=-291$$

Steps for Solving Linear Equation

Multiply 30 and 5 to get 150.

$$150+5a=0.9\times 30+0.9\times 5\left(a-5\right)$$

Multiply 0.9 and 30 to get 27.

$$150+5a=27+0.9\times 5\left(a-5\right)$$

Multiply 0.9 and 5 to get 4.5.

$$150+5a=27+4.5\left(a-5\right)$$

Use the distributive property to multiply 4.5 by a-5.

$$150+5a=27+4.5a-22.5$$

Subtract 22.5 from 27 to get 4.5.

$$150+5a=4.5+4.5a$$

Subtract 4.5a from both sides.

$$150+5a-4.5a=4.5$$

Combine 5a and -4.5a to get 0.5a.

$$150+0.5a=4.5$$

Subtract 150 from both sides.

$$0.5a=4.5-150$$

Subtract 150 from 4.5 to get -145.5.

$$0.5a=-145.5$$

Divide both sides by 0.5.

$$a=\frac{-145.5}{0.5}$$

Expand \frac{-145.5}{0.5} by multiplying both numerator and the denominator by 10.

$$a=\frac{-1455}{5}$$

Divide -1455 by 5 to get -291.

$$a=-291$$