Let x be the amount the woman invests in the 15% bond, then the amount she invested in her CD is given by $60,000 - x.
The interest she receives from the 15% bond is given by 0.15x while the interest she receives from the 7% CD is given by 0.07(60,000 - x) = 4,200 - 0.07x
Giving that her total annual interest is $6,000, then

Therefore, the amount of dollars she will be able to invest in her CD is $60,000 - $15,000 = $45,000